Assembler errors are divided into command line errors and assembly time errors.
For a command line error, the message is displayed after the invocation line. Some command line errors appear with an error number; these are described in the Section called assembler error messages. The other command line errors are:
| Error on File | system file error |
| File Conflict | The file name shown is being used multiple times as an output file, or an output file name is the same as the source file name. |
| File Not Found | The file name shown cannot be found. Possibly the wrong extension has been assumed or it resides in a different directory. |
| Disk or Directory is full | No more room exists to create an output file. |
| No Source File | The command line must contain at least the source file name. |
| Source File can't be a Device | The source file must be a disk file. It cannot be a device such as the console (CON). |
| Expected an option | An option must start with a /; file names must be separated by commas. |
| Can't nest indirect | files An indirect file (@file) cannot be nested inside another indirect file. |