Hi! Please also pay attention that you are using svnadmin.exe packaged with VisualSVN Server in order not to have problems with different svn format.
To do that please run the above command line from the VisualSVN Server Manager (VisualSVN Server Manager->Command line). Another way is to run svnvars.bat (something like "с:\program files\VisualSVN server\vsvnvars.bat" ) before the upgrading process to set path to the svnadmin.exe from our distribution. -- Regards, Olga Dolidze VisualSVN Support
