Windows Installer cannot be accessed

rraod · 14 Oct 2011

There is a manual method of getting back the windows installer up and running, which is explained in Microsoft Support website..

Method 1: Reregister the Windows Installer

Though this method is given for Windows XP and Windows Server 2003, I am not sure whether this method works for Windows 7. Still there is no harm in trying this for Windows 7 x64 as a last resort before you reinstall windows.

The attached image shows the locations of the windows installer file "msiexec.exe" on my windows 7 x64. The backup location for "msiexec.exe" is C:\windows\winsxs folder.

There are two "msiexec.exe" files in winsxs folder. 32 bit and 64 bit versions.

1st step would be to locate the msiexec.exe files in Windows\system32 and windows\sysWOW64 folders.

If these files are not present due to the fact that you have uninstalled windows installer, copy the first four files from winsxs folder to the bottom four locations given in the attached image.

2nd step would be to enter the registry values.

3rd step would be to re-register the msiexec.exe file.

Reboot and go to Windows Services management snap-in and check the startup type for Windows Installer is set to Automatic.

Method 2 given in the website does not apply to Windows 7 as the Windows Installer 5.0 is not available as a separate download.

seavixen32 · 14 Oct 2011

You can download the Windows Installer here: Download Details - Microsoft Download Center - Windows Installer 4.5

Although it is the 4.5 version, it works with Vista, so it may do for Win 7 as well.

rraod · 14 Oct 2011

Windows 7 Includes Both Windows Installer 5.0 and Windows Installer 4.5

Windows Installer 5 for Windows 7

These two links explain the differences in Windows Installer 4.5 and the latest 5.0.

starstorms · 14 Oct 2011

Well, after an absolutely unbelievable hassle and at least 20 straight infuriating hours trying these and quit a few more suggestions I finally decided to give up and go to the option I hadn't even considered at first and get the original install disks. This was another hassle but I was finally able to use those and do a repair in place install.

Even that only sort of worked, now I'm in the process of reinstalling pretty much every major program on my machine because they all started acting very strangely or just not working but with different error than before.

My suggestion to anyone having this much difficulty with this issue is just to do a clean install. You'll have to reinstall most major programs anyway.

Thanks for the help guys.

gregrocker · 14 Oct 2011

You might still need a clean reinstall if the Repair Install resulted in such a mess.

It sounds like you had major corruption and/or infection.

starstorms · 14 Oct 2011

That's a fair point... however, my mental capacity and sanity to continue working on this has been completely drained. It has also put me significantly behind on my work project as I have made no progress in the last two days thanks to this and I will have to work all weekend on that alone to catch up as I have deadlines to meet.

gregrocker · 14 Oct 2011

Take your time to check performance and let us know how it turns out.

starstorms · 14 Oct 2011

I've actually done about a dozen clean installs so I'm not scared about it but as long as things are working properly I need to get some actual work done.

Thanks for the support though!

seavixen32 · 15 Oct 2011

You're very welcome.

Please post back if you encounter further problems, although a clean install should settle the issue once and for all.