During saving file I'm getting information "Invalid Symbol Table name error". Problem is already known so i tried to follow the instructions given to other users by you. I've tried to change spaces to _ symbol in the layers names or deleting polish specific letters but there was no change. I was able to find out that the problem is related only to four layers named: A_ciany... When I delete these layers I'm able to save file without error message. Can you tell me what's wrong in these layers? I've tried to change names of these layers but problem still exists. Best regards.