Hi RSWallis,
Based on your description, could you tell me if this issue occurred in particular file or all files? Have you ever tried to open it in safe mode?
First please try to open excel file in safe mode, if it works fine please check the add-ins in your excel.
Click File > Excel Options > Add-Ins on the left side of the dialog. Then click the drop-down arrow at the bottom of the dialog box and select "COM Add-Ins" from the list, then click the GO button. What comes up is a list of COM-Add Ins that
are loaded and running.
In order to stop them from running, uncheck the boxes next to the COM add-in and then click OK. Now go back to what you were doing in Excel and if the crash no longer happens, the problem was one of the COM add-ins you had loaded. You can narrow the list
down by re-checking COM add-ins in the list until you find the culprit.
Then if it still crashes in safe mode, trying the following list of possible resolutions:
Method 1: Verify/install the latest updates
You might have to set Windows Update to automatically download and install recommended updates. Installing any important, recommended, and optional updates can frequently correct problems by replacing out-of-date files and fixing vulnerabilities.
Method 2: Check whether your antivirus software is up to date or is conflicting with Excel
Your antivirus software is not up to date, Excel may not function correctly.
Method 3: Check whether your file is being generated by a third party
Sometimes Excel files are generated by a third-party application. In this case, the files may be generated incorrectly, and some features may not work correctly when you open the files in Excel. If this occurs, test the features in new files outside the
third-party application. If the features work correctly, you should make sure that the third party is aware of the issue.
I provide 3 methods, and you can get more specific information from this link:
http://support.microsoft.com/en-us/kb/2758592
And you can also refer to this article:
http://blogs.technet.com/b/the_microsoft_excel_support_team_blog/archive/2012/04/12/excel-hangs-or-becomes-unresponsive-when-saving-or-closing-a-workbook.aspx
If this issue still exists, please let me know and could you be a bit more precise explain your problem so that we can get more accurate solutions to this problem.
Im glad to help and follow up your reply.
Regards,
George Zhao
TechNet Community Support