Same problem here, no offline IM at all since July 4th 1pm secondlife time. Discussed this problem at a forum and found out many people with different internet provider have the same problem, so its not us (not our email provider) its lindenlab (their server system) that has the problem. I did a ticket today about it, however at the forum someone else also did a ticket and got no help of LL, they only said it might be a single problem. Harms my business in the big way, I can only hope the problem gets solved somehow.