I think it often has to do with partially entering a new line. In @MarkKotyla's example, if you had specified a Job # on line 2 but then blanked out the Job #, you'll get that ""G/L Account is Required"" message upon trying to get off that line (e.g., tabbing/entering thru). I've experienced this in 4.30 G/L if I mis-key something and therefore the system thinks I'm entering a new line, of which the G/L is in fact required for a new line. So the only real option is to delete the line. Also have gotten this message in 4.30 G/L if I'm entering a line that has the same G/L account as the previous line, because even though the G/L Account defaults from the previous line, you don't seem to be able to just enter/tab thru it; you have to re-specify the Account #.