The most reliable source for the software is the forums or archived driver sites.
: A comprehensive archive of legacy versions (0.97ja to 0.98D5) is maintained at Shrubbery.net KEE Electronics Willem Pcb50b Software Download
: A reliable archival source for the programmer files, including necessary system drivers, can be found on this Willem EEPROM Programmer GitHub Archival Start CD The most reliable source for the software is
The Internet Archive holds a snapshot of the original developer’s FTP. Search for "Willem EPROM Programmer PCB50B CD Image." This ISO file contains the exact software that shipped with the board in the 2000s, including: including necessary system drivers
Navigate to SourceForge and download the file. Extract it to C:\Willem .