For newer LOGO with encrypted PW there is an other option.
1. program an other LOGO withe a program protected by a known PW
2. start a readout of the LOGO with the known PW
3. when prompted for the PW unplug the cable from the LOGO with the known PW and plug it in the LOGO with the unknown PW
4. write the known PW in the still open PW dialog
5. the program from the protected LOGO is read out
Tested with LogoSoft 8.2