Some years ago I purchased a locally made program which has run on Windows 98 successfully. However, I recently upgraded to a Lenovo laptop with Windows XP installed and whenever I attempt to start the program a message appears saying the program is already active and should be closed. However, I have checked and the program is definitely not active. I spoke with the person who wrote the program who says it is caused by Windows XP but is unable to fix the problem. Do you have any ideas?

As you have commented that the program is not running, I assume that you have used CTRL-ALT-DEL to check that the program is not running in the background. Since the person who wrote the program is unable to suggest a solution unfortunately I do not have any additional ideas about how to fix the problem. I suggest that you continue to work with the software programmer to see whether this problem can be resolved.