Excel 2013/2016/2019/2021/365: Slow startup/shutdown; fix corrupted Excel toolbar file (Excel15.xlb)

Question

- We have an issue that "excel.exe *32" stays running for a long time when we shut down Excel. Excel.exe stays open and won't close automatically.

- Excel holds onto memory even though Excel has been closed. Each Excel document that is opened creates another memory capture. The only way to release the memory is to end the process. This did not happen until a recent upgrade to Excel 2013 was performed.

Answer

Occasionally, the toolbar file (Excel.xlb or Excel15.xlb for Excel 2013, 2016 and 2019/365) for Excel can become corrupted. If this occurs, you may experience problems when you start or close Excel.
In this situation, locate the toolbar file, and then rename it. After you rename the toolbar file, Excel rebuilds a new toolbar file the next time that you start Excel.

To rename the Excel toolbar file, follow these steps:

1. Close Excel.
2. Locate the Excel15.xlb file.
   Notes:
   By default, the Excel.xlb file is located in the following folder:
   C:\Users\AppData\Roaming\Microsoft\Excel
   In Windows 7 and later, the xlb file is found by entering this into the Windows Explorer's address bar:
   %AppData%\Microsoft\Excel
3. Right-click the Excel15.xlb file and then click Rename.
4. Type Excel15.xlb.old, and then press ENTER.
5. Start Excel again.
6. (In addition, we've also got reported that sometimes a restart of the computer was required.)

The Excel.xlb file stores changes to the Ribbon. These changes include buttons that are added by add-ins.

A few resources about this:
https://support.microsoft.com/en-us/kb/919196
http://www.jkp-ads.com/articles/startupproblems.asp
http://support.cch.com/kb/solution.aspx/sw886