Can anyone help with this problem I came back to from over the weekend? When I try to open Reddcoin Windows qt 1.3.1.2 it says:

Assertion Failed!

Program: C:\...reddcoin-qt.exe
File: src/checkpoints.cpp, Line 285

Expression: mapBlockIndex.count(hashSyncCheckpoint)

What does this all mean and how do I fix it? I have very recent backups of my wallets just in case. Thanks!