There are following steps for resolution.
Step 1: Clear the files from XLSTART folder
Step 2: Open XLSTART folder from the following location.
\Users\<username>\AppData\Roaming\Microsoft\Excel\XLSTART or removed Excel12.xlb
Many time can't see AppData folder hidden. How to unhide it?
i) Start Button > Control Panel > click on Appearance and Personalization.
ii) Click on Folder Options > go to the tab View > check Hidden files and folders: Show all files and folders.
iii) Click on Apply and OK.
Step 1: Clear the files from XLSTART folder
Step 2: Open XLSTART folder from the following location.
\Users\<username>\AppData\Roaming\Microsoft\Excel\XLSTART or removed Excel12.xlb
Many time can't see AppData folder hidden. How to unhide it?
i) Start Button > Control Panel > click on Appearance and Personalization.
ii) Click on Folder Options > go to the tab View > check Hidden files and folders: Show all files and folders.
iii) Click on Apply and OK.