had same problem too

Spring Harvest, Anunnaki1,
i believe the message you have received said:
Dear (nickname), there was an error with completing your quest! Information about this error will be copied in to exchange buffer after closing this window. Please, sent this information via e-mail, forum or skype to our Administration. You can insert this information in to letter by using keys CTRL+V or clicking the right mouse button and selecting "paste". Thank you.

Should you face similar issue again, please follow these instructions.

I have had this problem as well. Although I tried to paste the information after closing the window, it would not paste anything from the game. Just what I had copied last from something that was not game related.

In my case it happened when I tried to open the experienced protector quest after having leveled up. Once I refreshed the game I had to go find the lizard and talk to him again, and everything seemed to be working fine.

Sir Truckula,
you don't have to copy-paste the actual letter, after the window is closed, all information goes to the buffer and then - to the letter. Anyway, i am glad to hear your issue has been resolved

Just so you know this same thing happened again last night. I had completed the elite protector quest which was a level 17 ghost hunter (elite). I am level 19. I got a notice for a new elite quest and when I opened it, this same warning popped up. Only thing I could do was refresh. Could not click OK on the message or do anything else. Once again it was not placed in my buffer to send. However after refresh the game gave me a new elite quest and proceeded normally.