Unable to update malware bytes

Last night, when i was surfing on the internet my anti-virus program has started giving me an popup saying updates are ready and need to download, when i try to update from the virus protection site it does not allow me update the file and the the update size remains same on the other end, when i recollect the day before event that time i have found some malware and my antivirus unable to remove it properly i ignored that and carry forward. The Malwarebytes sends a message about Trojan.FakeAlert.H being present.

To enable the automatic update go to internet explorer > tools > internet options > connections > settings > tick at 'automatically detect settings' only

Here you may have the MB with the latest definitions..

http://www.malwarebytes.org/mbam/dat...mbam-rules.exe

You are infected with a polymorphic file infector. This infection can and will infect all the machine's executable files .exe, .scr, .rar, .zip, .htm, .html.It was just our luck that our server was the only one located close enough to whatever was causing the power issue that it had to be shut down. Because there are a number of bugs in its code, it may create executable files that are corrupted beyond repair resulting in an inoperative machine.