but the problem is the logfile is a bit dynamic and i dont know what errors i am going to get. i just know that "--" usually indicates an error but not all lines with "--" means that they are really errors. so in this sample log file

Well then, your first step is to find out either what you want, or what you don't want. No regular expression is going to solve that one for you.

Thanks for taking the time to properly format your post. It is most appreciated.