MAPI Spooler could not be started. Close and then restart all mail-enabled applications

If there is a problem to send excel file to Mail Recipient and getting error "MAPI Spooler could not be started. Close and then restart all mail-enabled applications" as per screenshot below, please try to perform the troubleshooting below:

Go to My Computer --> C:\WINDOWS\system32, rename mapi32.dll to mapi32.dll.old and run fixmapi.exe found in the same folder.
This will created a new mapi32.dll file and you should be able to send excel file as per normal.