Disk usage C:/

I see that my c:\ disk space used is 90 GB out of the 99.9 GB capacity as seen in Disk properties. I have done a disk cleanup, emptied recycle bin and emptied the contents of temp folder. When I add (sum) the hiddn folders and the unhidden folders'sizes in C drive like Program Files, Program Files(x86), Windows, Users, etc, it sums up to 65 GB only. So, how can I find where the remaining 30 GB is consumed. Any inputs / suggestions?
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

JohnBusiness Consultant (Owner)Commented:
Use Tree Size Pro (Jam Software) as top of class to organize and see your disk usage. Run as Administrator after you install it.

Are you doing backups to your disk?  This chews up space.

Also, 100 GB is really not enough for an OS install with software and data.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Windirstat does the same thing but is free. It will tell you what files and folders are taking up the most space. You also have to take in to account your swap file and hibernation file.

Kerr Heilee AlmarioCommented:
Tree Size will find all the missing storage you're looking.
You can also delete the files in the software directly.
Sometimes, temporary folder stores most of the big files you have in the computer.
Active Protection takes the fight to cryptojacking

While there were several headline-grabbing ransomware attacks during in 2017, another big threat started appearing at the same time that didn’t get the same coverage – illicit cryptomining.

David Johnson, CD, MVPRetiredCommented:
The key item that you have to do with any disk space program is run it as an administrator. this allows the program to access the entire drive not just the files that you have permissions to access.
Alan HendersonRetired marine engineerCommented:
Did you run Disk Cleanup as Administrator?

That allows you to remove additional system files (old install backups for instance) which often consume a lot of space.

Jackie ManIT Manager Commented:

Have you removed system restore points also?

Windows 7
You cannot delete an individual restore point, but you can either delete all restore points or all but the most recent restore point. Deleting restore points temporarily frees up disk space. As new restore points are created, disk space will be used again. For information about how to adjust the disk space that is used by restore points, see How much disk space does System Restore require?

To delete all but the most recent restore point

Open Disk Cleanup by clicking the Start button Picture of the Start button. In the search box, type Disk Cleanup, and then, in the list of results, click Disk Cleanup.

If prompted, select the drive that you want to clean up, and then click OK.

In the Disk Cleanup for (drive letter) dialog box, click Clean up system files. Administrator permission required If you're prompted for an administrator password or confirmation, type the password or provide confirmation.

If prompted, select the drive that you want to clean up, and then click OK.

Click the More Options tab, under System Restore and Shadow Copies, click Clean up.

In the Disk Cleanup dialog box, click Delete.

Click Delete Files, and then click OK.

Source: http://windows.microsoft.com/en-hk/windows/delete-restore-point#1TC=windows-7

Do the above only if your system is stable and you do not need to have access to the previous versions of files saved in C drive.
what os is this? it can simply be full - 90 Gb is not very much disk space...depending on installed software + data

you can also run a chkdsk to repair files ystem errors
MikeIT ProfessionalCommented:
No comment has been added to this question in more than 21 days, so it is now classified as abandoned.

I have recommended this question be closed as follows:

Accept: John Hurst (https:#a41665837)

If you feel this question should be closed differently, post an objection and the moderators will review all objections and close it as they feel fit. If no one objects, this question will be closed automatically the way described above.

Experts-Exchange Cleanup Volunteer
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Storage Hardware

From novice to tech pro — start learning today.