PRB: Resolving "Cannot Load PROAPI16.EXE" Error in FoxPro

• Microsoft FoxPro for MS-DOS, version 2.0

SYMPTOMS

The "Cannot load PROAPI16.EXE" error message is displayed when you use the Extended (32-bit) version of FoxPro for MS-DOS.

CAUSE

There are three main causes of this error:

1. The PROAPI16.EXE file is not in a directory listed in the AUTOEXEC.BAT PATH environment variable.

2. The CONFIG.FP file contains the DOSMEM=ON statement.

3. There is not enough free conventional memory available on the system.

RESOLUTION

The corresponding resolutions for the causes above are as follows:

1. Make sure that the directory containing the PROAPI16.EXE file is listed in the PATH environment variable in the AUTOEXEC.BAT file.

2. Modify the CONFIG.FP file to include the DOSMEM=OFF statement, or comment out the DOSMEM=ON statement in the CONFIG.FP file.

3. Modify the CONFIG.SYS and AUTOEXEC.BAT files to free as much conventional memory as possible.

MORE INFORMATION

PROAPI16.EXE is a memory manager used only in the Extended version of FoxPro version 2.0. It loads into the lower 640K of RAM to make conversions between 16-bit application programming interface (API) libraries, BIN routines, and the 32-bit Extended version of FoxPro.

In the Extended version of FoxPro, DOSMEM=ON causes all available conventional memory to be used as additional extended memory. Since the 16-bit API uses conventional memory to perform its 32-bit to 16-bit translation, DOSMEM=ON prevents the API from being loaded.

If an application for the Extended version of FoxPro uses an API function, the PROAPI16.EXE file must be distributed with the application. For example, when printer drivers are included in an application, the GENPD.APP file must be included in the project and marked as Excluded.

GENPD.APP contains library files that can be loaded only into conventional memory. When FoxPro runs in Extended (32-bit) mode, PROAPI16.EXE provides a way to access these library files. Because the Standard version of FoxPro runs in 16-bit mode, it does not require any conversions; thus, the PROAPI16.EXE file is not required.