Microsoft refuses to fix known Excel bug
A bug with the popular Microsoft Excel program has been driving users crazy for years but Microsoft continues to release patches and new versions without fixing the bug.
The bug can be seen by opening an excel file and selecting the contents of a cell and selecting copy or "Ctrl" + "C". Then using "Windows Explorer" double click on another excel document that you wish to paste the information into. The system will stop and not respond to the request forever.
Currently, the only way to get the system to respond is to go back to the document that the information was copied from and select another field. Instantly the system will respond and take whatever actions were attempted.