I created a test installation using InstallShield version 11. This installation has one object (Microsoft VC++ 8.0 CRT) . I install this version successfully. I then created a test installation in InstallShield version 2008. I used the same product GUID as the first installation. I create a differential update installation pointing to the first release media on the IS11 installation project. I then install this differential update to the installed test installation. It installs successfully. I then attempt an un-installation. It errors with a -5009 exception. If I don't include the object in the first installation, then the un-installation will not error! The same error will occur in IS12 also. However, if the first installation was built with IS12 and the differential update built with IS2008, then the un-installation will work correctly. So is this a known bug? BTW, this is a Installscript installation.
This has been confirmed as a "bug" by InstallShield technical support. Current workaround is to use a full release for updates vs. differential updates. I am waiting for a hotfix for this problem.
