Error 1723: Can not uninstall JRE update X from Windows 7

I came across this today whilst helping one of our install techs update Java for a customer on a machine he was installing.

It was Windows 7 Ent 64bit SP1 with Java v19 installed.  Upon attempting to uninstall he received the error:

Error 1723: Can not uninstall JRE update from Windows 7.

After a bit of digging around I discovered the error was referring to a missing DLL.

By going into the registry and finding the MSI entry I tried an uninstall using the following command:

msiexec.exe /x{26A24AE4-039D-4CA4-87B4-2F83216019FF}

This was found here: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall   -  this is a great tip for any app packagers needing to discover the msi registered to a piece of software for uninstalls etc...

Again I received the same error message.  To enable error logging I added /L javauninst.log and discovered it was missing the "regutils.dll" located here: C:\Program Files (x86)\Java\jre6\bin

I copied the file across from an existing machine and voilà - it worked !

Another Java/MSI quirk but non the less slightly perplexing to say the least. 

Hope this helps someone else sometime...

C