Many times when using CVS under Windows XP, I have the problem that a “cvs update” fails to update some file or the other without any apparent reason. Turns out that this is because the file in question is open in some application, which, for some reason has thrown out a dialog-box with the file held open waiting for my input (usually some simple yes/no query). I have this happen typically with source code browsers. A quick way to figure out if the file that didn’t update is being held open by some application is to use the Windows “openfiles” command. Go ahead, run it on the command line and check it out. It’s a neat command that serves a simple purpose. Note that you need to run “openfiles /local on” to turn on the monitoring of open files and that the monitoring has a performance impact.