Hello summerchase,
Welcome to bytes.com!!!
Please remember to provide a meaningful Title for any threads started (
Please Use Appropriate Titles for New Threads!). This helps to ensure that other members, and also the general public, will have a better chance of finding answers to any similar questions.
About your question:
Does the window (that cannot be closed) has a X button. Many programs simply do not have X button to close. If it has, then the application is either not responding or it is refusing to close due to some bug/intended internal coding of program. You can try running task manager and then right click the process and click "End task" (or something like that).
In any case, I can only think of a solution if you post more information about the type of program that you are trying to close, your basic system configuration etc.
Thanks......
AmbrNewlearner