When I checked my C:\CodeBlocks directiory it had completly removed codeblocks.exe and replaced it with Addr2LineUI.exe.
Well this is
not done by Code::Blocks, but by your system or any weird software you are running (maybe you AV solution).
C::B does not and even cannot silently remove
codeblocks.exe. If that happens, something else is the reason. Find out which process removes the executable.
You can also try to copy the
whole installation once it is installed
completely into another folder (maybe under "my documents") and try from there. Code::Blocks is "portable", so actually you can safely copy it to any place you like and run it from there. You may then remove the original installation, if you like. See if that helps.
But again: Its definitely not a C::B issue, if during night (maybe due to a AV/sync/backup task run scheduled every midnight) executables are being deleted. Also, you seem to be the only person that has such an issue.