Hello my friend.
this is my story about this problem.....
Trigcom is 1 of 2 carriers in Norway that sells BB and has a dataplan.
Trigcom struggle with simcard error for almost a year.
After escalating the problem to RIM, Trigcom was told to send one of the simcard they used. After a few months they tried a new kind of simcard, but still got simcard error.
(Trigcoms contact person in rim (carrier relationship manager) told that the guys working on the case x-rayed the simcard and god knows what else to solve the problem
)
RIM released 2 os updates within this year that they told should solve this problem, without success.
Now for the first time in one year Trigcom is free for simcard error on 8700g (that was most common to have simcard error). Except a few incident where all hope is given up, and the device is changed.
But this is a worst-case-scenario.
But in your case try to turn the device on/off with out pulling the battery.
Or just pull the battery. Simcard should not be necessary.