Thank you for the link. I'll look at it in detail when I have the time.
Please do. There are two important workarounds/fixes in that article that you should try.
As for the D+ Logs: Well I could, of course. But I doubt it would help you... I looked at the logs myself but the only relevant entry I could find was about the attempted change of an important registry key from an OpenGL test program I compiled earlier. I cleared the log and tried compiling again but no Entry was made. Not even something that would seem irrelevant. Just nothing.
This is also the reason why I am not completely sure yet, that the problem originates from Comodo. But it is the only reason I can think of. Before I installed Comodo it worked fine. On the other hand, this problem didn't occur immediately after I installed Comodo. This is all quite strange.. I will try to reinstall CodeBlocks and maybe even Comodo (although I really want to keep my settings).
What configuration are you using? Look under More --> Manage My Configurations to see what the active configuration is.
You mentioned FF not being able to download. Is that for each and every file you are trying to download or only for specific sites?
Also make sure that your previous security solution is properly uninstalled. Use the manufacturer's clean up tool. You can find it here:
http://kb.eset.com/esetkb/index?page=content&id=SOLN146 . Having a leftover driver or service of a previously installed security program running can cause all sorts of weird and unexpected behaviours.