User32.dll is a standard Windows Dynamic Link Library, that contains such functions as window size and positioning, user messages, menu states and clipboard formatting. It is included with all versions of Windows.
The message you are seeing probably relates to the version of this file that you are using. This shouldn't happen with standard apps, like Office97, but may happen with third-party software that installs its own user32.dll.
Search your hard disk for copies of user32.dll. The one Windows uses is in \windows\system32. If there are other versions on the disk, and the locations are in the system's path, then Office may use one of these instead. If the version Office is using does not have appropriate functions defined within it, Office will fail.
You could try renaming versions that are not in the \windows\system32 folder. Do not delete these, however, or you may cause further issues with your computer.
It is curious that this should suddenly come about if you have not installed any software recently - is the machine on a network that receives regular anti-virus software updates? Has anyone else on the network seen this issue? Doe anyone else use this computer? What Screen Savers are installed - apart from the regular Windows ones? Do you regularly access the internet?
My only suggestion would be to uninstall then re-install Office, if this is an option to you.
I hope this information is useful.
