How to enable Ossn error reporting

From the administrator panel proceed to:

Site Settings -> Basic -> Error Reporting

When switched to On Ossn will start writing errors to a file named error_log in the root of your Ossn installation.

If your screen appears to be so much corrupted that the administrator panel is unusable, there's another way to turn on error logging from outside:

Simply create a file named DISPLAY_ERRORS in the root of your Ossn installation. Make sure the file is named exactly this way: all capital letters and no file extension.

Read https://www.opensource-socialnetwork.org/wiki/view/1101/how-to-report-a-bug and provide the lines which have been logged to the error_log file.