Hi There,

I see large .msp files in C:\windows\installer\  directory. Please let us know if we can safely delete the .msp files that are older than six months. If so, would deleting the file have any other impact to the stability of the OS?

Also, would deleting the files cause any of the security updates to get rolled back?

Thank you in advance for your help,

V

No, these should not be deleted. 

Refer : http://support.microsoft.com/kb/2667628

Thank you Arnav for your help. Kindly let me know what is the best way to cleanup unused/orphaned files in installer directory. I understand they are required, but there are some I reckon are orphaned; which I believe can safely be deleted. Please let us know if there is way to tell which of those are orphaned.

V

Disk cleanup : http://windows.microsoft.com/en-au/windows/delete-files-using-disk-cleanup#delete-files-using-disk-cleanup=windows-8

Hi,

I agree with the answer that you cannot remove the files in the Windows\Installer directory.

In addition, as this directory is used by the Windows Installer service to cache installer data files for various applications and it is also used by the application to confirm the existence of previously installed items to determine the next steps the installer needs to take. The files are different from machine to machine, so you cannot copy them from other machines if you delete them.  

Removing files in this folder may cause application crashes, or you may need to reinstall the application.

If you want to reduce space in this directory, the proper way would be uninstalling the unneeded applications.

Best regards,

Susie

• Edited by Susie LongMicrosoft contingent staff, Moderator Thursday, October 16, 2014 9:03 AM
• Marked as answer by Susie LongMicrosoft contingent staff, Moderator Monday, November 10, 2014 9:51 AM

Mine has > 9 GB with files going back more than 4 years, and I find it hard to believe they are all really needed. The answers above, which boil down to "just leave them cause you need them" are not satisfying.  I use every app on my machine so uninstall not an option.  If I really do need all that crud then someone (you lurking Microsoft?) needs to provide a more satisfying explanation why.  Else someone please provide an intelligent rule/method/algo/utility to clean this up.

PS:  I have already uninstalled many apps, and since run ccleaner64; Windows 7 64, 8GB RAM, 500GB HDD with 150GB free.  Thank you for any help.