Angsuman's WordPress Guard Plugin issues

For some reason Angsuman’s WordPress Guard Plugin stopped prompting me for its login even though it was listed as activated. I tried to deactivate with the intention of reactivating it but every time I would click “deactivate” I would be taken to my blog page. I deleted the file manually and re-uploaded it and now it’s listed as deactivate but I can’t get it to activate now. Anyone else having this problem? If so what can be done?

Also are there newer and/or better plugins to help secure my WordPress blog from hackers?