Missing userdata file

I bought PVZ Game of the Year edition on steam yesterday but when I open it, it shows Error Writing User File: Can't read user file whenever I want to type the username.I did some research but sadly found out that the userdata folder never exists and also, when I looked at my steam data folder, there's not even a 3590 folder(the steam appID of this game) folder under it. PLS HELP!