Haven't seen a raw.txt file for years, but never associated with Item Collector that I recall. If you want to look at it, WordPad should be able to open it or any sized file. Notepad is very limited and even Word / Word-clones are somewhat limited.
I googled "raw.txt" and couldn't find anything relevant, so personally, I'd just deleted it, as the name implies it's a temporary or repaired file to me. If you delete it, and Item Collector quits, working, I'd uninstall Item Collector then re-install it.
Just some ideas, don't take them as absolutes that will work though.
Yther Ore.