Hi Klaus,
I don't think this is a hardware problem. It might be a defective OpenGL implementation. Do both machines have the same graphics card? Which brand? Can you update graphics drivers?
It could be anything else. An antivirus blocking or messing with file I/O operations, a defective device driver, a virus, a utility software running as a background task (typical problems caused by 'helping' utilities distributed by brands such as Dell), an issue with file permissions on the disk or folders you are working on, another application taking control of folders (this happens frequently when you work on a folder controlled by file sharing and cloud storage applications such as Dropbox), etc. Windows is so obscure that anything is always possible in unexpected and inextricable ways.
