eror message when i work on the tags section

I get this message when i'm creating or moving tags:

 

how i can fix it?

i re-install acrobat but it not solve the problem

By @Ronen David

I had this problem too (Mac) and the error dialogs would cascade... sometimes dozens needed to be closed by clicking the "OK" dialog button (only possible action) for each one. GRRRR! 

I found a solution that works for me... close the "Object Properties" window after each time editing your Tag/s. Also, remember that Tag type labels can be changed via cut and paste. I have a text editor open with the Tag types (ex: <LBody>) that I am using so I can paste them in to the Tag types in the structure tree instead of opening and closing the "Object Properties" window each time.