I am reading all of these comments and becoming quite disheartened as the exact same problem happened to me. I wish now I came here (my judgment mistake!) rather than contacting Malwarebytes by email to their support. I wrote to inquire if I shoud delete the MP43DECD.dll and MPG4DECD.dll and the other two that showed that they were Registry files, and someone at Malwarebytes named Larry replied that it was okay to delete them. Now, I am learning that I should not have done that. So far I have been able to view Youtube and I have a DVD in playing, but it looks like I am not able to get the files back via a system Restore. I have a Windows XP computer. Larry wrote that I can expect more issues because my computer is XP. Now, come to find out here that these all were False Positives! So, I guess if I can't restore them or reinstall them somehow (doubt if Microsoft will help me out on this issue since I have Windows XP), like someone else here wrote we are just out of luck. So, I have learned a valuable lesson about the value of just leaving some things in Quarantine until you have checked everything out including come here! Thank you.