This one at least includes a content id - I'd suggest contacting the postmaster at the receiving site and ask ..
Easier perhaps if you contact the person you emailed, out of band (say over the phone), quote him that incident id and have him get his email admin to check > > Technical details of permanent failure: > PERM_FAILURE: SMTP Error (state 12): 554 5.7.1 Message rejected > because of unacceptable content. For help, please quote incident ID > 40699249. >
