I have a Nokia 6210 which is displaying "SIM error STOP". I have tried
known good sim cards from all 4 networks. I have also run Eeprom Tools
v4 and the 6210 is passing the various tests so I think the eeprom is
not corrupt.

I get the "SIM error STOP" message a few seconds after switch on -
there is no other messages such as "Registering" etc.

With no sim installed , I get the usual "Insert Sim" message.

I have searched the net but not found any answers.

Maybe the 6210 needs to be reflashed? Maybe its a hardware problem? I
checked for obvious problems but nothing stands out. The internal
backup battery was a bit corroded and was reading 1.7v. Maybe the
corrosion indicates some water damage but the PCB looks clean. The LCD
is missing a horizontal line at the top but I don't think this is the
cause of the "SIM error STOP" message.

Any thoughts?

Thanks