Mysterious IIS crashes

We recently started experiencing a few site crashes but there were no obvious errors, but after some investigating one of my colleagues (nicknamed the Wolf) stumbled across this error message:

DCOM got error "Overlapped I/O operation is in progress. " and was unable to logon .\IWAM_BOB in order to run the server:
{3D14228D-FBE1-11D0-995D-00C04FD919C1}

He dug a little further and found the solution to the problem (look for the post by yakhunter). For posterity here is the resolution.