I have a customer who had a power outage, after this power outage they've been experiencing calls dropping (all analog lines). 1 phone only, intermittently loses it's button programming. I've reset all trunk cards and trunk mods, then system. Still same problem, I've upgraded to 5.0, thinking the power outage corrupted the data. Same problem with calls dropping, the 1 phone that was losing button programming is now ok. I can't figure this one out, I've called Nortel and they seem to think the configuration programming files are corrupt and the corruption followed along with upgrade and are reccomending a "System Startup" and programming from scratch. I'm hoping not to do this as this is a rather large system and wil keep the customer down for sometime. Has anyone experienced this?