Compiler out of memory - Available compiler memory for symbol space, buffers, and so on, has been exhausted.
If no more memory is available, separate your program into a small main program which uses the #INCLUDE metastatement to include the rest of your program. You can also try the following steps:
Remove unnecessary line numbers and labels.
If your code includes WIN32API.INC: Try adding the "code exclusion" equates such as %NOGDI = 1 to your code to cause the compiler to ignore large sections of the API file. Please review the first few pages of notes in WIN32API.INC for more information.
Alternatively, create a customized version of WIN32API.INC that contains just the definitions and declarations actually used by your code. The latter solution, whilst more work initially, will have the added benefit of much faster compilation times, and make your code more resistant to changes in subsequent releases of WIN32API.INC.