Patch fails with 'PackageCode {GUID} is not unique'

[JohnO]

I am exploring the Patch process, by simply changing one of the XML files that our application uses. But the patch process fails. I don't have a separate IA project for the change. This is how the simple patch is done in the white paper.

I have found two forum entries for this from some years ago. As far as I can tell, I am doing all the good things right.
http://www.installaware.com/forum/viewtopic.php?p=6566
http://forums.installaware.com/viewtopic.php?p=17194&sid=7e829a032f8ed8547f864c6632fb2865

The previous two lines in the log and the error message:

Processed base package E:\IA_Workspace\RSS22\PROGNOSE-Installer\Patch\Base Package 2\Romonet Software Suite 2.2.msi
Creating patch E:\IA_Workspace\RSS22\PROGNOSE-Installer\Patch\Romonet Software Suite 2.2.msp
Error during build: Unable to create patch database [TargetImages.Target = 'TARGET2': PackageCode {27297FFF-D2E5-439A-B6A9-8D1FDDEE9363} is not unique.]

My build script has '/r' to ensure the rev code is updated, and /pr points to the previous build.

I have just found a '.msp.log' file in the 'Patch' folder. The last message is:

ERROR: UpgradedImages.Upgraded = 'UPGRADE': ProductVersion is not valid.

My version is defined by a compiler variable, which us set in the build script. So, to see what happened I changed the Version entry (for 2.2) from #VERSION# to 2.2.01 in the Project Properties page. Saved the project and then reran the script. This time the error message in the log is exactly the same (i.e same PackageCode - whatever that is? However the error message in the .msp.log changed to:

ERROR: TargetImages.Target = 'TARGET2': PackageCode {27297FFF-D2E5-439A-B6A9-8D1FDDEE9363} is not unique.

I can also see that the Patch folder contains a new folder 'Base Package 2'. So, it looks as though more progress was made.
What do I need to do?

Regards, John

[FrancescoT]

Dear John,

please have a look at the following topic;
http://www.installaware.com/forum/viewtopic.php?f=2&t=9656&hilit=+patch

I suppose you are not using the correct approach required to create a patch.

Regards