To test for and eliminate the possibility that a third-party Excel add-in or file is causing a 'save' problem in Excel, try to save the file in Safe mode. However, some functions, such as saving a file can be affected.
Typically, these third-party add-ins do not interfere with Excel functionality. Some add-ins from third-party software vendors work together with existing Excel features by design, and some are intended to enable a seamless transition when you use a third-party product. By default, startup files are loaded when you start Excel. If you cannot save a workbook when you run Microsoft Excel in Windows Safe mode, the problem may be caused by a third-party add-in or by a file from one of the Excel startup locations.
