We have a situation where all appears to be fine, until a user tries to retrieve their messages and get the Failsafe Prompt. An administrator changed the wav format in Registry and then tried to put right ... I get the following errors. A few mention to check in drive H:, which we don't have !! Tried to run SetWaveFormat and see if it makes a difference, but nothing. Deleted accounts, created new, left messages, MWI on, but still failsafe prompt. Unity 4.2 win2k3 + Sp2, + lots of eng specs. Any ideas gratefully received. Chris.