User can't uninstall...

[JHC Software]

I have a problem with a user not being able to install an upgrade. The info is second-hand, but I'll try and get more if required.

Here what I belive the situation is.

The user downloaded an msi file, but this was corrupted (only half of it downloaded)... so this wouldn't install (fair enough).

The user now has an uncorrupted msi, but tries to install but it says that it can't and displays (in the user's words) "unable to delete the prior installation". The original installation isn't shown in Add/Remove programs, so he can't uninstall it manually.

Any suggestions how to resolve this so the user can install the updated version (e.g., delete some reg entries, or repair the old installation somehow?).

So far, this is the only user with these problems.

Many thanks.

[UdreaMihai]

Hi,

Can you send us the exact message that appears when the user tries to install the new version?

Normally, a corrupted MSI can't be installed. I suppose that the installation was fine but the user might have made some Registry changes or other unusual things.

If the user still has the original package, he can perform a Repair installation and then try to upgrade the application with your new package.

Waiting for your reply.

Best,
Mihai.

[JHC Software]

I've asked the user if he can try to perform a repair with the original package and see if this fixes it.

I'll also try and get the exact message that's displayed if I can.

[JHC Software]

The message the user is getting is "unable to remove older version".

I'm not sure if the user knows what previous version he had installed was, so getting the correct .msi file to him so he can try to repair it is a bit of a problem just now, but we're still trying.

Any ideas how to resolve this if the original installer isn't available? Presumably there is some registry entry somewhere that could be cleared perhaps?

[UdreaMihai]

Hi,

You can erase all the data pertaining to an installation, using Msizap.exe (from Platform SDK). But you can't remove the files or registry keys which were created by that application.

In order to erase that data, you need the Product Code of that application.
The Product Code can be obtained by opening the MSI file with ORCA or the AIP file with a text editor, but only if you know which MSI package the user used when he previously installed your application.

If you can obtain the Product Code of the package installed on the
user machine, here is a link to find out more about Msizap.exe:
http://msdn.microsoft.com/library/defau ... ap_exe.asp


Hope it works.

Best,
Mihai.

[JHC Software]

I sent the msizap utility to the user with a batch file to remove all possible previous product versions of our product and this worked for him and he was able to install a new version.

Once again, many thanks for your help.