Hi -

I downloaded MacKeeper, thinking I was doing a good thing. I tried to remove it, but don't think I did it properly. I've noticed my MacBook seems to be slower since then. How can I be sure I really removed it?

Thanks.

A Google search for "uninstall MacKeeper" points to many links similar to your problem.
This Link (http://applehelpwriter.com/2011/09/21/how-to-uninstall-mackeeper-malware/) appears to be very popular.

I do not recommend installing any version of MacKeeper. It resists removal, and it is widely reported to report false virus positives to scare you into paying $40 for it. Other reports are that it compromises machine performance (as you have found) and can even delete data files.

More information is here
Q. How do I remove MacKeeper? | CanadaRAM: Memory and Computer Q&A (http://www.computer-answers.ca/2012/computer-questions/macintosh-questions/q-how-do-i-remove-mackeeper/)

I've found the best way to remove it is to cold boot into Safe Boot Mode which stops the MacKeeper daemons from running and then use the suggestions provided to use "EasyFind", and I also use "Find Any File" as well, and then do a search on 'zeobit' and 'MacKeeper' and all the appropriate files/folders can be Trashed or immediately destroyed which bypasses the Trashcan.

Then restart normally.