Somehow I constantly cannot save the work as I receive next error. As a rule initially when starting work with the model the saving possibility exists, but after  a while the saving option dissapears. Only one chance is to save if I  close the simulation then I am offered to save the work and interestingly the work is saved.

As it is seen this kind of working routine is not acceptable.

I have copied the files on my local disk the problem is the same

. 

Please help

Jaanus