VMS Help UIL, Compile Time Errors, SRC_OPEN  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  SEVERE:  The compiler could not  open  the  UIL  specification  file
  listed in the message.

  USER ACTION:  Check that the file listed in the message is  the  one
  you  want  to compile, that it exists, and that you have read access
  to the file.  If you are using a large number of include files,  you
  may have exceeded your quota for open files.