July 31, 2009

Windows Installer Tips, problem installations

With installer issues it's always difficult debug problems. If it's the Installer itself i.e. work done in the setup.vdprj itself then you maybe in a spot of bother. There are some logging options which are available to you.The other problem you may have is with your Custom Action if you have one. This maybe easier to diagnose, asyou can use the Visual Studio Debugger to attach but this in itself is not always easy todo.
If you have problems with your installer itself and not the Custom Action then try this:You can also Log installer actions by activating the installer logging, this is done through a registry entry, http://support.microsoft.com/kb/223300. All your doing is adding a "String Value" named "Logging" and a value "voicewarmupx" to the registry entry HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\Installer
I've done this and found some useful info but it's not that easy to read, at least it tells you the command that was ran and where it got the installer from.
If you have problems with your Custom Action then try this:
In your Custom Action's code add a Debugger.Break() or a MessageBox.Show() , build your projet in Debug, launch your msi and when the messag appears you can then attach to msiexec.exe.
I've found that the Debugger.Break does not always work, the MessageBox.Show should always work, just gives you a chance to attach your debugger.
Common problems with the Custom Action
Common problems with the Custom Action are the use of the SavedState IDictionary, trying to use entries that do not exist. I recommend wrapping everthing in a try/catch and then rethrow everthing in a new InstallerException, I usually add one for each method in my Custom Action.
catch(Exception ex)
throw new InstallerException("There's a problem with the installation", ex);

Also check for nulls everywhere, unit tests are the best way to find these.

Cannot uninstall
Another problem I've found with the Custom Action is if your installer has a bug that doesn't allow you to uninstall then your in a bind, how can you fix it if you cannot uninstall it. The solution is usually to find the bug by attaching the debugger and then fix it, but you still cannot use it, yes you can but you must copy the fixed Custom Actions dll into the installation location. The uninstall actually calls the dll and not just the msi so by updating it with the fixed on you can fix your uninstall.

To Force an uninstall
try this
MsiExec.exe /I installer.msi REINSTALLMODE=voums REINSTALL=ALL
installer.msi is the name of your installer.
The Repair/Remove dialog will appear and you can then Remove.Got this info from http://labnol.blogspot.com/2007/06/windows-installer-issue-when-programs.html
There's also this Windows Registry Cleanup tool, I don't like this however as it cleans the registry making your application disappear from the users point of view but the files etc still remain, it's not really a solution if your about to reinstall.