Bug: Repeated indexing with a suspected corrupt index

After install of 4.0a it will index for about 4 hours...then the icon disappears..reopen L4 and it starts the indexing over again...it has done this at least 4 times.

Software version: 4.0a 4533.
Reported by Dave Hooton.
Forum link: https://logos.vanillacommunities.com/forums/t/7700.aspx
Status: fixed in 4.0b