I have a working 4.60 version installed on my computer. Now I want to run a 4.51 version on the same computer. Is this possible? When I try to run the 4.51 page I get this error: "The located assembly's manifest definition with name 'EPiServer' does not match the assembly reference" The assembly's in the GAC are all 4.60 versions so I think the problem is there. Do I have to uninstall the 4.60 version and install a new 4.51 version to get this work? Any ideas?