Doesn't work, errors out with this message:
"xxx.csproj appears to be read-only or not accessible for some reason."
This file is not read-only...the whole project is checked out and not read only.
What is the use of something like this if it won't ever work?
If you're talking about a upgrading a project that checks out with TFS. Upgrade the project on your machine locally, then check out with TFS.
Elizabeth from the Infragistics Team answered a similar question here that has more detail: http://forums.infragistics.com/forums/p/53617/277886.aspx#277886