Samsung's Buildpmt.exe program is an old DOS program that converts VOX files to PMT files for SVMI-e series voicemail systems, such as the SVMI20e.
Buildpmt.exe will not run in 64 bit Windows version such as Windows 10 or Windows 7.
I found a program called DOSBOX that will solve this for you.

1. Visit and download the dosbox program. Install it.
2. Put buildpmt.exe, bp.bat, and your vox files all in a folder such as c:\temp
3. Launch dosbox.
4. In the dosbox program, mount the c:\temp folder as your C drive by typing mount c c:\temp
5. Switch to your C drive by typing C: in the DOSBOX window.
6. Run your desired dos commands, such as buildpmt.exe or the bp.bat file I created. Example: bp 1001
7. You're done! Your new SVMI prompt files are now located in the folder you mounted. Close the DOSBOX program and you can now work with your files.

Here are the contents of bp.bat:
buildpmt /d%1.pmt /v%1.vox /e200

To use the bp.bat batch file:
1. Insure that the vox file you created has a file name of the desired prompt number and a .vox extension. Example: 1001.vox
2. Put this vox file, buildpmt.exe, and bp.bat all in the same folder on a machine.
3. Using the DOSBOX instructions above, type "bp {promptnumber}. Example: bp 1001
4. The bp.bat batch file will execute the buildpmt.exe file with the proper command line structure.