Question: There are two extra files in my Cookies folder called Mm256.dat and Mm2048.dat. What are they? 

Answer: .Dat files are Data files, usually used by one or more programs. They usually store information necessary to run/operate a program. If after dumping your cookies folder, they are still present, I would suggest running an anti virus program. If you want to know what they contain, try opening the files one at a time in either notepad or wordpad, then you can scroll through them and see what the text contains. There will likely be a good amount of gibberish, computer code that note/word pad cannot translate as written text. There really should not be anything in your cookies folder except cookie files (and sometimes media settings files). My best suggestion to you is to run a good anti virus program such as Avast! Home Edition (it's free). The link is to C|Net's download site, where you can get the free home edition fo Avast!
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