That is one of the annoying things about the Impression that I never had to deal with on my Razr. I generally have to delete all messages, and then reboot my Impression when that happens. It's usually about every other day.
Supposedly this is happening to ALL impressions but is not a known issue yet. A thread was already established about this issue and it may be due to the number of the sim card??? I am not sure if that is correct but I just would just power cycle it and wait a few minutes then try again. It will not be resolved until the manufacturer is aware of this problem in my opinion.
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