If there is an error during starting, a recoverable alert will appear
and show a number. Here is a list what these numbers mean:

Workbench-Start:
1: No memory for CLI-Structure
2: CLI-Table 20 limit
3: No current directory
4: No icon.library
5: No icon
OpenWindow:
10: Already opened
11: Cannot open output
12: Not interactive
13: Cannot open input
Newcli:
15: Cannot copy CurrentDir
16: Cannot set up pipe process
Input:
20: Input failed
21: Unexpected window closure (harmless)
22: Forbid or Disable state (bug in external command)