It could be that some file in the betfair folder was infected(or should I say Malwarebytes thought it was infected) and thus was delete or quarantied(sp?).
Check the quar. list in Malwarebytes or simply reinstall Betfair.
If neither of those two solutions work, then it's a bit more complex problem(ldo

)
However, if everything else has connection, it's almost cerain it's Betfair itself.
Backup if you need to(anything from betfair folder) and reinstall.
GL