The following steps will resolve this issue:
1. Launch SOHO Notes and choose SOHO Notes > Preferences, and click the Services button.
2. Click the General tab and disable the Service.
3. Launch the Terminal application (/Applications/Utilities/), and type the following exactly and press return:
unlink ~/Library/PDF\ Services/Save\ PDF\ to\ SOHO\ Notes
4. Switch back to SOHO Notes and enable the Service.