Thank you for your message.
This issue might be occurring if the Viewer's configuration file or address book file was somehow corrupted, perhaps, by some anti-virus software activity.
Please try the following and see if this helps to resolve the issue:
1. Obtain a backup copy of your address book by one of the methods described in this tutorial
2. Fully exit the Viewer File -> Exit
3. Locate the file config_4.xml
in the C:\Users\[Your_username]\AppData\Roaming\Remote Utilities Files\
Please note that the AppData folder might be hidden by default in which case you need to enable "Hidden files and folders" in Windows Explorer settings.
4. Remove the config_4.xml
file from that folder.
This will reset the Viewer settings. Your address books won't be affected by this action.
5. Run the Viewer and register it with your license key again.
6. Restore your address book from the backup file you have obtained on Step 1. You can follow this guide
on restoring your address book from a backup.
7. After restoring your address book try connecting to a remote Host and the password works this time.
Hope that helps.