Unable to get solution id from manifest error

Sep 25, 2008 at 9:51 PM
Edited Sep 25, 2008 at 9:54 PM
I get an error when I choose the Upgrade option using the WSPBuilder add-in fro Visual Studio 2005 - trying to upgrade the solution.  The error is:  Unable to get solution id from manifest.  I can call stsadm -o upgradesolution OK from the command line and I don't get an error.  It seems like the solution is actually deleted or retracted or something, because when I try to upgrade some of the provisioned files are deleted but not replaced by new versions.  I think the solution does get upgraded OK but why am I getting that error?