I recently backed up my data and I had moved the vnc viewer executable from my PC to my portable hard disk. Realizing that I no longer had vnc, I got the latest one, but all of a sudden I could not connect to my server anymore and got authentification failure. So I moved the VNC exectuable back from my portable HD to my local HD. And I am still getting Authentification failure errors. I had a certain setup and I don't want to re-create it, do you know how I can recover or what happened to get auth failures all of a sudden ? I checked and the vncserver process is running fine. Old VNC viewer: vnc-4_1_3-x86_win32_viewer.exe New one: