Silk Test Classic calls LogError automatically when it raises an exception that you have not handled. By reading 4test.inc you can find that Silk Test Classic has a list of exceptions like:
E_ABORT = -10100, E_TBL_HAS_NO_ROW_HDR = -30100, E_WINDOW_NOT_FOUND = -27800
Since exception numbers can apply to more than one exception, it can be helpful to query on a particular exception number via ExceptNum() to decide how to handle an error. If you need to query on a specific exception message, you can use ExceptData(). We recommend using MatchStr() with ExceptData().
To find the E_... constant for any 4Test exception, you can use:
[-] do
<code that causes exception>
[-] except
[ ] LogWarning ("Exception number: {[EXCEPTION]ExceptNum ()}")
[ ] reraise
This will print out the exception constant in the warning.
Be sure to remove the LogWarning do..except block after you have found the E_... constant.