First check to make sure that the input module isn't opening "minimized". Check the task bar and if you see two CAESAR II icons, right-click on the right-most one and then select "maximize".

If that isn't the problem, use Windows Explorer and try to delete the CONTROL file. If you can't, you have a permission problem and that is why CAESAR II can't manipulate the file.

Also, if your data directory is on a network, another user may have ownership of the CONTROL file. This is why everyone working in a shared network directory needs to set the "USER_ID" in the Configuration Module.