I have 1.4.1 wallet and followed every step in this guide to upgrade to 2.0 version wallet ... i got daemon error in both cli and gui wallets.
 1.4.1 is still working and fully synced but shows block height 173547 and the official pool is at 166,303.

I got to say thank you for MA8R80 for making that video guide but it could be done much more simpler and shorter.