Review of "Stellar Toolkit for Outlook" by Andrew Leniart

Andrew LeniartIT Professional, Freelance Journalist, Certified Editor
IT Professional - Helping others to help themselves. &
This is a comprehensive review of a bundled Toolkit designed for use by IT Professionals and End Users to help Microsoft Outlook fans manipulate Outlook files and repair some common problems. Enjoy...

UPDATE - The "Stellar Outlook Toolkit" has recently been updated with a new name "Stellar Toolkit for Outlook" and now includes even more features. Rather than write a totally new review of this product, I've included a new section at the bottom of this article which describes the new feature(s), as well as the differences I've noted while re-testing all of its functions.

If you have already read this review, please skip down to the heading titled "Stellar Toolkit for Outlook" for a discussion and review of all the new updates and changes.

As the owner of an IT Support Providing company, I often get instances with clients that have developed problems with their installations of Microsoft Outlook, and subsequently look to me for help.

I have tried many free and commercial solutions, but the free ones rarely cut the mustard, and some of the commercial products I have tried to date fell short in some way. So, I finally decided to give “Stellar’s Outlook Toolkit” a run.

This article is a recount and review of some of my experiences and tests of the product.

Stellar Outlook Toolkit includes many features, including Repairs of PST Files, Splitting large PST files, Compacting, Converting OST to PST, Merging PST Files, Recovering PST File passwords and a tool to remove Duplicate Mail. As it claimed to do it all, I must admit it made me a little sceptical at first.

After installing and opening the software, you get presented with the following interface.

Stellar “Repair PST File” Module

I had a Corrupt Outlook PST file which I'd already repaired using another tool I owned. The corruption indicated that the PST file I was sent by a client was "not an Outlook data file (.pst) when I tried to open it, but I knew it was, so I decided to test if Stellar's solution could repair it. Clicking on the "Repair PST" icon, I was presented with the following;

I first use Browse (1.) to enter the corrupt Outlook.pst file into the utility, then clicked the Repair (2.) option as shown above. Note that the "Find" button simply allows you to find where the .pst file you want to repair is located in case you're not sure where it's located.

Clicking the Repair button started the repair process as shown below, with relevant progress bars.

Once the repair process completed, I was presented with the following result.

(Note that any identifying information has been blurred out in the image below to protect the PST owners privacy)

I then decided to Save the Repaired file as indicated below and was presented with a variety of options. I decided to "Save as PST" and to "Save PST Normally" from the advanced options and clicked the OK button to complete the save.

The following screens were then presented to me

Clicking the How to import PST file? Hyperlink brings up a useful Help File from within the software itself to give easy to follow instructions.

Having closed by clicking the OK button in the second image after the repair, I went back to my Outlook and tried to open the repaired PST file and was pleased to find that the PST file had been repaired correctly, with all Email messages and folders intact.

Pleasing also to note was that it left the Corrupt PST file intact in case anything went wrong with the repair and that it just renamed the repaired file as "corrupt@domain.local Repaired.pst" An excellent result and the process was very easy indeed, with no technical knowledge required.

Encouraged by that result, I next decided to try out the Split PST function on a PST file of my own that was close to 2GB in size.

Stellar “Split PST File” Module

Clicking the Splitting a PST File option presents you with the following screen.

Clicking the Drag & Drop to add PST presented me with a standard Windows 10 folder/file selection window, so I selected a PST file I had that was just over 1.6 GB in size. Once selected, I was presented with quite a few helpful options to Split the file with. See the next screenshot.

I decided to go with the “By Date” option and in the “Date Range” then selected Between 1st Jan 2017 and 1st Jan 2018 for the Date Range and clicked the blue “Split” button. Stellar Outlook Toolkit went to work on the process and provided a neat little animation that assured me something was happening while I waited. 

It’s a good thing that it did too, as the operation did take some time to complete and I would have been concerned that nothing was happening without it!

At the end of the process, I got the “Splitting completed.” Message and Stellar created a folder named “StellarSplitter_24-03-2018 20-34-06” in the location I’d specified which contained an “Outlook Split.PST” file that was 405,993 KB in size! The original PST file was left untouched, which gives the opportunity to split it again using different splitting criteria.

I opened the split file in Outlook 2016 and was pleased to find that the split file did indeed only contain messages from 1st Jan 2017 to 1st Jan 2018. All folders were intact, and the PST file performed flawlessly. Even my Contacts and Notes were those that had been entered between the dates I created. Well worth the wait for the process to complete and a tool that can be invaluable if you want to split your PST files into certain dates for organizational purposes. Brilliant!

Compacting a PST using "Stellar Compact PST" Module

To test this function thoroughly, I first made a copy of my 1.6 GB file and performed a Compact function on it using Outlook’s built-in compacting tool.

Compacting Results using Outlook's "Compact Now" Function

  • Before Outlook Compacting – 1,621,937 KB 
  • After Outlook Compacting – 1,502,153 KB

I then restored my original uncompacted PST file and ran the same process using the “Stellar Compact PST” function. The first thing that happened was that I was advised that an add-in had been added to my copy of Outlook.

Clicking “OK” gave me a series of different compacting options to try. To make the test fair and comparable, I selected the following options for this compact test after adding my Outlook.pst file into the windows presented:

  • Compress all attachments in new PST file
  • Remove unused space (this was selected by default)
  • Empty ‘Deleted Items’ Folder
  • Empty ‘Junk E-mail’ folder

And then I clicked the “Compact” button. Note that Outlook needs to be closed during this operation.

Once again, the software provided a neat little animation to show that things are happening while you wait for the process to complete. Once again, a good thing it did, because the process took considerably longer than Outlook 2016 built-in compacting function.

After compacting had completed, Stellar provided the following screen, with a helpful link to how to import the compacted file back into Outlook.

Compacting Results using Stellar Compact PST function

  • Before Compacting – 1,621,937 KB 
  • After Compacting – 1,169,337 KB

So, in summary:

  • Outlook's Compacting Results: 1,502,153 KB
  • Stellar's Compacting Results: 1,169,337 KB

An additional saving of 332,816 KB by using Stellar Outlook Toolkit to compact rather than Outlook’s built-in compacting tool. This goes to show that Stellar does a much better job of it!

I did try the other options available with the Stellar Compacting tool, such as;

  • Extract and save attachments to a folder (No interlinking is lost)
  • Extract, compress and save attachments to a folder (No interlinking is lost)
  • Remove all attachments in new PST file

And though the results were “considerably” better than just a straight compact operation, I’ve not included them in this review because Outlook does not provide such advanced features.

A warning note for those using Stellar Compact PST with a
Microsoft Outlook 365 subscription.

Stellar Outlook Toolkit ran into problems with this (and only this) compacting function when tested on my Office 365 Subscription package and crashed when it tried to compact my PST.

After spending several hours troubleshooting the crash with Stellar’s excellent Support staff, including them logging into my system remotely, it was finally found that the problem was with Office 365 itself and not with the Stellar Compacting module.

A portion of the concluding reply from Stellar support is included below;

"We would like to inform that you are using the subscription version of the MS Office 365 which is not a stable release from Microsoft and that's the reason Microsoft keeps on releasing the regular updates for it.

We recommend you to use any standalone version of MS Outlook. You can even use a standalone version of MS Office 365."

To verify the above for myself, I did install a standalone version of MS Office 365 into an Oracle Windows 10 Pro Virtual Machine to test the theory, and it turned out Stellar Support was perfectly correct.

The Compact PST function worked perfectly in a standalone version of Office 365 Outlook 2016.

Stellar "OST to PST" Conversion Module

An OST (Offline Storage Table) to PST conversion is a very useful function if you plan on disconnecting from an Exchange or IMAP server for good, or if you want to make a local backup of your OST file. I gave Stellar OST to PST a run to see how well it would perform. Here’s how it went…

Clicking the OST to PST option presented me with the following screen.

I browsed to the location of my OST file and then clicked the Convert button as suggested.

The conversion process went a lot quicker than I expected and at the end of it, I was presented with a host of information about the contents of my OST file, and given the option to “Save Converted File” at the bottom left of the screenshot.

I clicked the “Save Converted File” and got some options about how and where I’d like to save the newly created PST file.

As you can see with the above screenshot, there are several options, but I decided to just leave everything as default and clicked the OK button. Here’s the result.

Once again, Stellar provided a helpful “How to import PST file?” instruction for those that aren’t familiar with that process. Happily, I discovered that my original OST file was left untouched and Stellar OST to PST Converter created a new file named “ Converted.pst.”

Upon opening the Converted PST file in Outlook, I found that everything converted and mirrored the contents of my OST file perfectly. So that function too, worked exactly as I expected. A great result!

Stellar “PST Merge” Module

Next thing to try was how well the PST Merge function would work. I had a couple of PST files that I often open, so decided to merge them to see how this all worked. Clicking the option in Stellar Outlook Toolkit gave me the following screen.

I decided to try the Drag & Drop method of selecting PST files this time, so using Windows File Explorer, I highlighted the 2 PST files I wanted to merge and dragged them into the above window. That gave me the following option:

After clicking the “Next” button, Stellar went to work, did the job very quickly and asked me where I wanted to save the Merged PST files. I selected a Temporary location using “Browse” and hit the “Merge” button.

Note there are also a variety of other options available to you at this point, such as Joining PST’s as separate folder structures, which also worked well. I went with the default to just merge the two to a new PST file and hit the “Merge” button.

Another nice animation to reassure me that things were happening and once the process was completed, I got the following:

Clicking the “Open folder” link took me to a folder in C:\Temp\StellarMergePST25-Mar-2018 04.04.42 where a new Outlook.pst file had been created. I opened Outlook, loaded the newly merged PST file and started examining it. Once again, Stellar Merge PST didn’t disappoint. All the folders from both PST files that I selected to merge were there, with all contents intact, including Calendar, Contact, etc. information. Sensational result!

Stellar “Recover PST Password” Module

I’ve never had very much luck with Password Recovery utilities, so I wasn’t too confident with the included Password Recovery tool in the Stellar Package either, but for the sake of completeness, I password protected my PST file to see if (and how long) the Stellar software Recover Password module would take to help me get my password back if I had forgotten it.

The Password I placed on my PST file was 7 characters long, contained both capital and lower-case letters, as well as a few numbers. It was not comprised of a word that could be found in a dictionary, rather, some random letters that I would use to create a password to use for protecting something important to me. I also did not tick the option to “Save this password in your password list” in Outlook.

Having set a password on my Outlook.pst file, I fired up the Recover PST Password module and loaded my file.

With very low expectations, I hit the “Find Password” button to see what would happen.

Within seconds, Stellar Phoenix Outlook Password Recovery identified 6 passwords, NONE of which were my actual password, yet ALL of them worked to open my PST file!

Not satisfied it could work that well, I decided to give it a much more difficult task and created a 12-character password, including 3 capital letters, 2 numbers, and a special character as well. I then put it to the test again. Here’s the password I used – Wdfr^sA8i3Wq for the second test.

Again, in mere seconds, Stellar Outlook Password Recovery presented me with a series of 6-character passwords that all worked to open my Outlook.PST file.

To say “I was totally amazed at this result” would have to be the understatement of the year!

Not a single other utility I’ve tried in the past, either free or commercial performed like Stellar’s solution. It makes me wonder what the point is for password protecting a PST file in the first place if a utility like this can crack it so easily. An absolute Thumbs Up from me for the Stellar Recover PST Password utility. Amazing performance and result!

Stellar “Duplicate Mail Remover" Module

The last thing to try was the Duplicate Mail Remover. This turned out to be a powerful little tool indeed.

Clicking the option inserts an add-in into Outlook in a custom Tool Bar.

Clicking the “Stellar Outlook Duplicate Remover” add-in button while in Outlook produces a scan window that looks like this:

Hitting the “Next” button provides you with a multitude of options to select.

An explanation of the various options is worthy here.

“Select Time Span”

Clicking this drop arrow allows you to select the period you want the Duplicate remove function to process.

“Select Action”

Select Action allows you to tell the Duplicate Remover what you want to be done with the duplicates that it finds, from moving them to the deleted folder, right down to just deleting duplicates permanently. See below.

I selected “Text,” “Subject,” “Sender Email,” “Internet Header” & “Attachment files” for my test.

I also opted to Delete (Move to deleted items folder) after clearing my deleted items folder first and then hit the “Run Process” button.

Here’s a snapshot of it working away after clicking the “Run Process” button:

At the end of the process, you get the following screen:

After clicking the OK button as shown in the top graphic, you get the opportunity to Save a Log of everything that was done in Text (.txt) format. I saved my log, and everything was listed as expected.

Having checked my processed Outlook file, all duplicates were indeed in my Deleted Items folder just as I wanted them to be. The process took a while to complete, however having checked the results thoroughly; I can verify that it works very well. Thumbs Up!

Concluding Remarks


  • Works with both Windows 7 and Windows 10 (both 32bit and 64bit)
  • Trial copy is available as a free download
  • Installation is a breeze
  • Has a very intuitive user interface that anyone should be able to understand
  • All tools work as advertised and can be updated easily by just clicking a button
  • The performance of the Phoenix Outlook Password Recovery tool is exceptional!
  • Supports Microsoft Office Versions 2016, 2013, 2010, 2007 & 2003
  • Maintains data integrity by creating a copy of all PST & OST files it works on
  • Supports saving with different File Saving Options such as Office 365, MBOX, PDF, DBX, HTML, EML, MSG, RTF, etc.
  • Excellent value for money for IT Professionals who need a Tool Kit that does it all
  • 30 Day Guaranteed Money Back Guarantee if it won’t do what you need


  • Trial copy only works with limited features until purchased
  • This kit is expensive for end users.
  • Problems noted with the Compacting module when using on an Office 365 Subscription model
  • No other cons noted after extensive testing of all of the kits modules!

The “Stellar Outlook Toolkit” was tested on the following System Specifications

Motherboard - Intel Corporation DH67CL (LGA1155) Version (AAG10212-208)

CPU - Intel Core i7 2600 @ 3.40GHz - Sandy Bridge 32nm Technology

RAM - Total Physical 20 GB – Type DDR3

Graphics - V243HL on AMD Radeon HD 5500 Series

Hard Disk Drive - Samsung SSD 850 PRO 512GB

Operating System - Windows 10 Professional (64-bit)

Microsoft Office 365 – 32-bit install

Authors Final Note and Disclaimer

Apart from being granted a valid Key for full functionality testing of this product, neither I nor my company (Andrews Computer Help Zone) has any professional affiliation with Stellar Data Recovery. I am simply a user of this toolkit. This product was tested and reviewed in late March of 2018.

The updated "Stellar Toolkit for Outlook" may be Trialled and Purchased using this link

Stellar Toolkit for Outlook

(An Update to my Review Above)

This product was recently updated to include another module which IT Support Technicians should find helpful, namely, Recover Deleted Emails software. I'll discuss my findings on this new module shortly, but first, let's take a quick look at the most obvious changes after updating/installing the product.

The first thing I immediately noted when I fired it up was the User Interface change. Opening the product now looks like this:

Though only an opinion that will be subjective to everyone, I consider the newly designed screen to be a considerable improvement over the last UI front screen, mostly due to the descriptions that are now included as to what each of the available modules does. Nice.

Clicking on the button gives you an "About" type screen with information about the current version of the product, some system information about your OS (which in my case was wrong - as I am using Windows 10 Pro, not Windows 10 Enterprise as reported), so this is something (minor) that I've let the developers know about that needs fixing anyway. Here's a snapshot.

Clicking on the "Compact Outlook PST" and "Remove Duplicate Emails" now bring up a message that tells you an Addin was added to MS Outlook and both of those modules now need to be launched from Outlook itself.

Here's how the add-ins looked on my own desktop copy of Outlook 2016 from my Office 365 Suite

Clicking on either Add-in above in Outlook brought up the same type of Window as already shown in my previous review above, and both worked just as well.

To ensure everything still worked the same way, I retested all of the following modules and confirmed I got similar results to before.

  • Repair Mailbox
  • Convert OST to PST
  • Merge Outlook PSTs
  • Split Outlook PST File
  • Compact Outlook PST
  • Remove Duplicate Emails
  • Recover Outlook Password

All worked as expected, so now it was time to fully test the new "Recover Deleted Emails" module. Clicking the new module icon gave me the following screen:

I first clicked the (1.) Browse button, located my Outlook PST file and opened it

Selecting the (2.) Find button brought up the following window

Clicking the "Find" button on the above screenshot, I was presented with the following results to choose from

I selected my Outlook.pst file in the above window and then clicked the "Recover" button.

The entire process took about 20 minutes, but I guess that's understandable given the quite large (1.8 GB) PST file I decided to test it on. At the completion of the scan, I was presented with the following window

Clicking "OK" and then the "Save Deleted Items" buttons as highlighted above, produced the following prompt

So I clicked OK on the prompt, closed my Outlook as suggested and then clicked the "Save Deleted Items" button again, which gave me the following window

I browsed to a Temporary folder to save in, selected PST as the format I wanted the deleted email saved in and hit the OK button. About 15 seconds later, I got the following notification

I then loaded the "Outlook Recovered.pst" file the software produced into Outlook and had a good look through it. Sure enough, a bunch of deleted emails, all the way back to 2009 that had been permanently deleted all existed in the recovered PST file that the software created. An excellent result.

Other options the tool provides that I thought were useful are shown below

The Find Message icon allows you to refine your search criteria when hunting through deleted messages to save you manually searching for what you're trying to find. Options are the To, From, Subject, and Date Fields, all or any of which can be used to refine your search. Once you've found what you're looking for, just right click on the message and save it as an MSG, EML, RTF, HTML, or PDF format. Very useful function.

The Save Scan and Load Scan icons allow you to save a scan you've already done so that you need not perform the same scan again.

Save Scan

Load Scan

More than one scan can be saved and kept for later use as can be seen from the above screenshot, so highly useful and provides some great time-saving features.

Concluding Remarks 

The newly included "Recover Deleted Items" Module in this kit should be well received by Support Technicians who make use of this Outlook Tool Kit bundle. Whilst the price of this kit is probably out of reach for most end users, the bundle of tools included should make it a worthwhile purchase for IT Support technicians who tend to do a lot of repair work for Outlook users.

About the Author

I am an IT Professional, Editor, Freelance Journalist and an all round good guy! :) 

You can contact me for additional information by simply accessing my Profile Page at Experts Exchange.

All contents of this review are ©Copyright 2018 to Andrew Leniart.

Andrew LeniartIT Professional, Freelance Journalist, Certified Editor
IT Professional - Helping others to help themselves. &

Comments (16)

Well written Article Andrew..!!
Andrew LeniartIT Professional, Freelance Journalist, Certified Editor
Author of the Year 2019
Distinguished Expert 2020


Well written Article Andrew..!!

Thank you for reading my article and endorsing it by clicking the thumbs up icon Clik. I  see you joined today so please also allow me to extend a warm welcome to the Experts Exchange community! :)

Regards, Andrew
Thank you so much Andrew.. :)
Basem KhawajaClinical Pharmacist


Thank you once again for another enlightening article that I am sure would love to use after reading a bit more about it and see if I can afford it. Do you think I need it for my Outlook based on what you know about my PC and Outlook over all?

Thank you Andrew,

Basem Khawaja
Andrew LeniartIT Professional, Freelance Journalist, Certified Editor
Author of the Year 2019
Distinguished Expert 2020


Hi Basem,

Thank you for your comment and endorsement. In answer to your question, yes you could benefit from this tool, but it's very expensive and aimed more at IT professionals that tend to repair a lot of Outlook problems for paying clients. I would suggest a cheaper package by the same vendor, however, due to your ever-increasing knowledge learning from the tips that experts have been giving you, I think that at this stage, it would be an unnecessary expense for you to spend buying this suite. You are slowly becoming a pretty good troubleshooter in your own right - keep on learning :)

Regards, Andrew

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