Just yesterday, I began having an issue on my work machine running Windows 8.1 x64 along with Chrome 41 BETA x64, Opera 27, IE 11.0.9600.17631. All download attempts fail with a virus detected warning (varies from browser to browser). The only browser that seems unaffected is Firefox 35.0.1 - the others listed above do not work.
I found a co-worker who has an eerily similar setup to mine. He's unable to recreate this problem. These changes were made to both of our machines yesterday:
February Patch Tuesday updates were applied
Definition update for System Center Endpoint Protection 2012
The other changes that occurred that I did uniquely were:
Ran 'powercfg.exe -h off' to kill the 26GB hiberfile.sys on my SSD
Ran cleanmgr.exe and cleaned user and system files
Ran cleanmgr.exe and removed all but most recent restore point
Ran 'dism /online /image-cleanup /analyzecomponentstore'
Ran 'dism /online /image-cleanup /startcomponentcleanup'
Moved the page file location to data drive
Troubleshooting steps I've taken so far that haven't worked:
I disabled real-time protection in Endpoint Protection
I verified that the Custom Level settings in Internet Options>Security>Internet were set to prompt for downloads
I reset IE as an administrator
The only way I've been able to get this to work is by locating that same 'ScanWithAntiVirus' value in HKLM and setting it to 1. Currently, that's what I'm running with and things are downloading as expected. However, I don't think that's a good way to go long term.
I've been a technician for many years and I've never really experienced any of the above things causing something like this. However, something obviously changed as I was downloading files just fine every day before yesterday.
Can anyone offer any insight into this? I would love to know what to do or to learn about some hidden pocket of settings. I don't want to just forfeit and refresh Windows if I don't have to.