An administrator reported that some of his users had problems with messages hanging in the Outbox and pressing Send & Receive crashed Outlook:
"Some emails sit in the Outbox and won't send. I've checked the settings and can't find anything. It's not affecting every message, just some. If we try a "Send All" Outlook crashes. After a restart, the messages will send. "
Problems with send and receive are almost always caused by corrupt send/receive settings. Go to the roaming app data folder, browse to \Microsoft\Outlook and delete or rename the SRS file for your profile then restart Outlook.
Windows 7 or Windows 8
The SRS file is located at C:\Users\username\AppData\Roaming\Microsoft\Outlook. You can access it by typing or pasting the following line into the address bar of Windows Explorer and press enter:
Windows XP or Windows 2000
Look for the SRS file at C:\Documents and Settings\username\Application Data\Microsoft\Outlook. Type or paste the following line into the address bar of Windows Explorer and press enter to access it:
A corrupt SRS file can also cause Outlook to crash when you expand the Tools menu in Outlook 2007 and older. (As will a corrupt outcmd.dat file.)