The System Log
Generally you should be able to locate error logs within different functions, such as terminated updates (as seen in SM13). In very rare cases you may know that a problem has occurred in your system, but you are unable to find out where or what the problem was, in these very rare cases you can always refer to the System Log with transaction SM21.
Select “Problems” from the selection parameters and view the results for a date/time range. Be careful though as not every “problem” highlighted in red is an issue worth analyzing. You need to know more or less the exact date and time of the error you are trying to analyze.