MacKeeper itself, has been known to cause system stability issues..
What i would like to do is first, have a look at this for verification
Then, lets uninstall mac keeper as follows.
Once its removed.. run this procedure next
To open Disk Utility, from the Applications folder, open Utilities, and then double-click the Disk Utility icon.
In the column on the left, click your startup disk.
Click the First Aid tab, and then click Repair Disk Permissions. Disk Utility will reset any files and folders with incorrect settings.
Then restart your mac.. And if its still acting strange, or giving any error messages, please let me know specifically what they are so that we can deal with them individually.
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