On premises Exchange migration to Office 365

I would like to hear from people who have moved users from on-premises Exchange to Office 365 mail.  In particular I would like to know about any feature loss that users complained about or any  negatives about administering Office 365 mail versus on-Premises Exchange.
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jhyieslaConnect With a Mentor Commented:
Yes, as far as I can tell, PF functionality should be about the same as on-premise. As I said, we're not totally done yet, so that's an educated guess mostly, but quite honestly, not much has really changed for the average user.

So, far no one has complained about the loss of any functionality in doing their jobs. A few shared mailboxes lost a full permissions setting that I had to put back in, but that was more the exception than the rule. We also have a relationship with one of our owners, where we have mailboxes for them, that they really can't use, but we use it to forward email sent to that mailbox to their corporate mailboxes. We lost some of that after migration. If I looked at the forwarding rule, it was still in place, but it's like it didn't get pointed properly to the contact that we have set up in our system with their corporate address.  All I had to do was to reset that on each account and it worked again.

There's a slight learning curve for people using the web-based Outlook. But we provided some decent documentation ahead of time and the questions have been relatively few.

As far as speed.  With the on-premise system we had the cached exchange mode in Outlook turned off. While this worked well for that scenario, it caused a huge amount of slowness in Outlook after migrating. So, we've told people to turn that back on and that seems to have solved the overall Outlook slowness. All email is stored in the cloud and so the first time in, it all has to sync down to the user's local machine, assuming he's using real Outlook.  We had a few people call us and tell us that they had missing email. It was just them being impatient as the Outlook status bar was stating that it was still syncing folders. Yes, there probably is a larger gap in time between sending and receiving an email because of this. But I've not seen it be so horrible that anyone would complain about it. Initially people with larger mail stores would see a longer time to sync, but I've not had any complaints about performance.

I can't comment on the caching. We've not had a loss of Internet connectivity. We also use a third-party email filtering system that is also cloud-based and should we lose connectivity for some reason, this product also gives us the ability to cache email and for people to actually sign into and continue to send and receive email. The same thing goes for archiving. We use this service to archive our email so I have no experience at all with the Office 365 version of that.

Since we're still in the set up phase, most of our questions have gone to the consultant company that we are using to help set this and other things dealing with Office 365.  We have had a question or two that's been out of the scope of the project and we've had to engage MS and that went OK...the consultant also had to engage them at one point and we got a decent response.

One issue that I, as an admin, find frustrating is making changes in the cloud and waiting for it to sync. We have an ADConnect server on premise that sync's our AD to the cloud. I've had two separate scenarios. One is that we have a number of people who also have access to some shared mailboxes. In the On-premise version, all I had to do was to give them the proper access and by the time I walked back to their desks to add the account to their Outlook, the permissions had become active and they could immediately see that account. Now, in the cloud, even if I am making the change in the cloud and they are using Mail in the cloud, it can take up to 30 minutes for that to become active as our sync is at 30 minute intervals. Even if I go to the ADConnect server and kick off a sync, it can still take 10-15 minutes for it to become active.

The issue for me is that I am the super admin for the exchange server. I have god rights to everything and I have access to everyone's mailbox. All I have to do is add it to my Outlook and I can see the email in that account. I use this mainly when management needs to know if someone is doing something they shouldn't with their email. If you look in the Full Access permissions in Outlook, I am on every account. I assumed, stupidly, that this would transfer to the cloud - it did not. So I've gone in as the main admin and given my account as many permissions as I can find. But still if I attach a user to my Outlook, I do not have access.  So, I have to go in to their account in the cloud, give myself the access and then wait for it to sync. Since I don't do this very often, it's not a major critical negative. However, once I add a user to my Outlook and then I go to remove it, it won't go away.  It's stuck there until I go back into their cloud account and remove the permissions I gave myself.  Then when it syncs, the account will disappear from my Outlook. It's very possible that I am just not aware of the proper way to handle this and I may be causing myself more work than is necessary, but assuming I'm not, I don't like the way this particular feature works.
MAS (MVE)Technical Department HeadCommented:
Vasil Michev (MVP)Commented:
You can get feature-by-feature comparison of Exchange Online vs On-prem in the following article: https://technet.microsoft.com/en-us/library/exchange-online-service-description.aspx
Creating Active Directory Users from a Text File

If your organization has a need to mass-create AD user accounts, watch this video to see how its done without the need for scripting or other unnecessary complexities.

Sajid Shaik MSr. System AdminCommented:
i found office 365 is the excellent hosting option, the only issue i face is the upload pst to office 365 ... but i managed it from outlook by copying e-mails from Exchange mail to Office 365 E-mail account... it'll takes bit time depends up on the internet speed...

the remaining things it's an excellent product...

easy Administration, and cost effective

all the best
Deeksha NegiServer AdministratorCommented:
Hi lineonecorp,

This topic has been discussed earlier on this forum.
Please follow the link below to know about the solution to your issue:

Peter HutchisonSenior Network Systems SpecialistCommented:
In a Exchange Hybrid mode, you can use the migration tools to migrate mailboxes to Office 365 instead of using PSTs.
Sharing of mailboxes and or calendars can be problematic between on-premise and Office 365. We found that it doesn't work that well, has anyone else come across this problem?
Jeffrey Kane - TechSoEasyConnect With a Mentor Principal ConsultantCommented:
To answer directly -- there are really no features which users would lose if you moved ALL users to Office 365.   There could be some issue with Calendar Free/Busy info if you did a hybrid deployment (keeping some users on premise and moving some to the cloud), but unless your organization is very large with 300 or more users, you probably won't be doing this type of deployment.

(Although using Hybrid as a migration method is quite nice if you are moving from Exchange 2010 or 2013 -- then you remove the hybrid config after you're done which eliminates any issues).

As for administration?  If you deploy Azure AD Connect (highly recommended) to sync user credentials between your on premise Active Directory and Office 365, you will have to administer most of the configuration for users in your ADUC console (if you like GUIs -- or through PowerShell).  The ADUC GUI method is a bit tricky if your users have multiple email addresses for their mailboxes.  In this case you will need to manually configure these on the Attribute Tab of their user object by modifying the "ProxyAddresses" attribute.

Other than that, its much simpler to manage than having an onsite server.  You will never have to do another service pack or update, you don't have to worry about integrating a 3rd party virus scanner, you'll never have mail stuck in your outbound queues, and you'll have infinite storage of all deleted items so you can recover them forever.
Jeffrey Kane - TechSoEasyPrincipal ConsultantCommented:
I should also note -- you don't have to use Hybrid mode to avoid migrating via .pst file as Peter said above.  You can use a cut-over or staged migration as well.  The native migration tools in Office 365 will connect to your Exchange server and pull over everyone's mailboxes automatically if you like.
jhyieslaConnect With a Mentor Commented:
We're mostly thru a migration from on-premise 2010. We are currently living in a hybrids environment. Mostly we have had very few issues and functionality between old and new is very good.

The main complaint that I have as an admin is administering new users. Our current process is to create the user in AD -one person does this. She will clone a user that the supervisor has designated as a match so that all AD groups get pulled in. Then she sends it to me and I mail enable them on the Exchange server. That process does not work with O365 even with the hybrid server in place. It appears that we have two options. One is for the AD person to continue doing what she does and then for me to mail enable them by running a powershell command to create a remote mailbox. The second is to completely create the user and mailbox at the same time in the O365 environment. The down side to this is there doesn't seem to be a way to copy an already established user or mailbox, so that would mean double duty for the AD person. MS does NOT allow you to mail enable an already established user in the O365 cloud.

We've chosen to do the former as this keeps the AD person doing what she knows how to do and doesn't alter her process flow and my process flow is only changed slightly.

There were also some minor issues with public folders, but the consultant we used took care of that so that cloud and on-premise users would have access to everything.  The only caveat as that as long as the PF's are still on-premise, users can't see them in the web-based Outlook, but they work OK in on-premise Outlook and once the PF's are moved, they should be good for everyone.
lineonecorpAuthor Commented:
Jeffrey Kane:

Thanks for the detailed response of the advantages.  It seems a lot of the other responders didn't bother to read the question and gave advice about migrating from Exchange, hybrid environments - not at all related to what I actually asked - the user experience and the administration aspect.

You write the following:

"As for administration?  If you deploy Azure AD Connect (highly recommended) to sync user credentials between your on premise Active Directory and Office 365, you will have to administer most of the configuration for users in your ADUC console (if you like GUIs -- or through PowerShell)."  Is there really no GUI interface from MS for me to administer Office 365. So for instance I have a new user and I create an AD account for them - there is no MS equivalent to Amazon so the mailbox is created and it's attributes set via a GUI from on-premises? I find it odd that I would have to rely on Amazon to integrated my AD and Office 365.
lineonecorpAuthor Commented:

Thanks for sharing your experience. It was exactly what I was looking for. The point about administration awkwardness is very good to know up front.  As far as Public Folders from what you can tell Office 365 would have the same functionality?

Also if you can detail any functionality loss at all it would be appreciated - sometimes there's an obscure function that in one organization only one person uses but in another everybody uses it so it's a big deal to lose. If you can think of any little 'loss' it would be appreciated.

A couple of other points.

As everything goes through the Internet have people noticed a slowdown in local mail?

Also do you have  off-line caching enabled and have you ever had to employ it because the internet is out and if so what was the experience for the users both during the outage and after recovery?  What happens with people with very large mail stores?

As far as archiving - any significant differences to that with on-premises Exchange and Outlook?

Finally one commenter noted that reponse time for problems after first signup was pretty good but slowed later? Have you had to call for support and for what kind of reasons and what was the overall experience?

Thanks for your further attention to this.
jhyieslaConnect With a Mentor Commented:
I did want to say that even though it may take 20-30 minutes for some change to sync, actual email delivery and the like happens a lot more quickly.
jhyieslaConnect With a Mentor Commented:
After I wrote the long email, I got to thinking about the issue that I have not being able to get to other user's mailboxes.  Again, it's not something that I do often, but when I need it, it would be a pain to have to go thru all those hoops.  So, I found an article about giving me the permission that I needed to do that.  It's a couple of PowerShell commands. I just got done running them and what it did was to add me to the full access permissions listing of each mailbox, but unlike me adding myself to an individual mailbox, it makes that mailbox available immediately and when I remove it from my Office 365 portal email account, it goes away right away and doesn't come back... so it functions like the old on-premise Outlook does. I haven't tried it in Outlook 2016 yet.  Here's the article:

Jeffrey Kane - TechSoEasyConnect With a Mentor Principal ConsultantCommented:
@lineonecorp --
Pretty funny... I decided to edit out of my response what you said about other answers.  (I'm trying to be less confrontational these days).  :-)

Anyhow... in Office 365's Exchange Online, a mailbox is only created when a license is assigned.  There is actually a GUI which will both create the user and assign the Office 365 license.  It will also sync credentials without using Azure AD Connect.

That GUI is called the Server 2012 Essentials Experience.  It is a free downloadable add-on to Server 2012 from Microsoft, and provides you with the same admin panel found on Server 2012 Essentials -- but not limited to that product's 25 user maximum.

So if you prefer this type of interface, you can certainly have it.

With regards to your comment about giving yourself full access to mailboxes and the mailboxes automapping to your Outlook profile.  You definitely want to use the powershell command to give yourself access (follow the instructions provided above inthe link jhyiesla provided) but add the following tag to the cmdlet:


This will prevent them showing up.  You can then either add manually to Outlook or use Outlook Web App to easily view.  

However, the better method to reviewing a user mailbox for policy issues is to use Office 365's Compliance Search (in the Security & Compliance Center) because this search will also show you items which the user may have "permanently" deleted --ie, deleted from their deleted items.  Because unless you change the default retention policy, nothing is ever actually deleted in Exchange Online.

Regarding your question about Microsoft Support.  If you submit a service request via the Admin Portal it will be acted on fairly quickly. I've always gotten a call back from their service concierge the same day the request was entered -- and that person schedules a time for a qualified support tech to call you.
Jeffrey Kane - TechSoEasyConnect With a Mentor Principal ConsultantCommented:
I should also comment on jhyiesla's remark about being frustrated waiting for things to sync when using Azure AD Connect.  There is a very simple way to avoid this -- just force a sync.

You just need to open an elevated PowerShell on the server running Azure AD Connect and issue the following two commands:

Import-Module ADSync

Start-ADSyncSyncCycle -PolicyType Delta

That will force a sync of anything that has changed since the previous sync (which by default is scheduled to occur every 30 minutes) -- and about 30 to 45 seconds later your Office 365 info will match your AD info.

If you want to force a full sync for some reason, use this command instead:

Start-ADSyncSyncCycle -PolicyType Initial
jhyieslaConnect With a Mentor Commented:
Jeff, yes, you are correct that one can force a sync, which I did mention in my main response. I've found that that it can still take a while for everything to get synced.  So, yes, it's faster, potentially than waiting, spending on where you are in the automatic sync cycle, but it's by no means fast; at least in my experience.
jhyieslaConnect With a Mentor Commented:
I also need to add that I discovered this morning that since I added in everyone with the powershell command, I now have everyone showing up in my Outlook, so, as Jeff says, I need to do the automapping  false
lineonecorpAuthor Commented:
Thanks for all the real world input.  Great help.
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