In drafting mode when I create a diameter the diameter symbol is missing, I get the <MOD-DIAM> label instead. And when I try to add the diameter symbol manually I get the error massage "Symbol library file (GTOL.SYM) is missing." ...
My SW revision is 2.0 BTW
This question comes up quite often.
take a look at this thread
GTOL .SYM is lost after updating to 2015
That solved the problem,
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