Micro Focus Visual COBOL 2.3 Update 1 for Eclipse (UNIX) > Deployment > Deploying to Enterprise Server > Enterprise Server Security > Securing an Enterprise Server Installation > Using External Security Facility (ESF) Features > ESF User Exit > Enabling an ESF User Exit > To enable a mandatory ESF User Exit

To enable a mandatory ESF User Exit

Ensure your exit module exists in the appropriate forms and has the correct filenames, as described in ESF User Exit File Names.
To force any process that uses ESF to use an ESF User Exit module, you need to place the module in the appropriate location with the proper name. If a module with this name exists, ESF will always use it and the configuration option for enabling the user exit will be ignored. The basename for the mandatory ESF User Exit module is saf_exit. For example, to make the referential integrity exit mandatory, do one of the following, depending on your operating system:
- Windows:
  Copy your 32-bit module to bin/saf_exit.dll and your 64-bit module to bin64/saf_exit.dll under your product installation directory.
```
cd C:\Program Files (x86)\Micro Focus\Enterprise Developer
copy bin\saf_refint_exit.dll bin\saf_exit.dll
copy bin64\saf_refint_exit.dll bin64\saf_exit.dll
```
- UNIX:
  Copy your user exit modules to $COBDIR/lib, using the destination name saf_exit followed by the correct suffixes.
```
cd $COBDIR/lib
cp saf_refint_exit.so saf_exit.so
cp saf_refint_exit_t.so saf_exit_t.so
cp saf_refint_exit64.so saf_exit64.so
cp saf_refint_exit64_t.so saf_exit64_t.so
```
You can also use symbolic or hard links in place of the copy statements, as permitted by your file system.
Restart MFDS and the enterprise server regions for the change to take effect. The region console logs should now contain messages indicating the exit module has been loaded and initialized.