The version utility checks for each file if it is write protected even if there will be no changes to that file. The check results are not listed at the end, but separate for each file. This is not a good user experience.
The version utility will do a preliminary check of your project directory, and it will identify any files that are read-only during this check. Since the version utility isn't aware of which files will need to be modified before it starts looking at the actual contents of certain files (for example, it needs to read the project file to see if there are any IG assemblies to update) , it throws an error.
We have chosen to throw an error instead of proceeding with the upgrade, since it may cause a serious issue if files are allowed to begin updating and one or more cannot be properly edited.
I encourage you to submit a feature request. We are always open to hear what you are saying about how we can improve our tools, and submitting a feature request gaurantees that Product Management will consider your request.
Thanks Mike for the reply. I just sent a feature request since I don't believe its "impossible" to improve the tool.
Uli