qperr.hlp (Topic list)
Important Notice
The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.
Error Message
 
Error 158:  Unit expected
 
A USES clause in a program called for a file that did not
contain a UNIT heading.
 
A used file must begin with a heading:
 
   UNIT <identifier>;