I was on the internet and a pop-up from McAffee told me the program blocked a trojan virus. A few minutes later the internet spontaneously shut down, and a string of pop-ups flashed and told me a write error occurred on my hard drive and needed to be repaired or my files would be lost. I did not trust, so I shut down and restarted. The pop-ups immediately came back. I tried to run a McAffee scan, but it wouldn't run and the automatic read, scan, and repair settings were off. I turned them on, and within 5 seconds they turned back off. This kept happening, then all my files, including internet explorer, disappeared. The files in the Start menu are gone. Tried rebooting in safe mode with networking and running a Windows Security scan, but while the scan says it's running, nothing happens. It scans a few files then loops.
Did I download a trojan? If so, how do I get rid of it?
Try a restore point a day or so back.
try this in safe mode.
Then download stinger and malwarebytes and superantispyware to a usb stick on another PC,rename the files and install them on your suspect PC. When installing rename the folder the programs want to create so the malware cannot see the programs and stop them.
See if they find anything.
Any name on any popup message?
"Security Tool" and "File Backup" were at the top of the pop-ups. I tried restore, I couldn't remember the password to log in as administrator, I tried repairing, and I tried using the task manager to identify the virus to delete it. The whole thing kept crashing, no matter what I did. So I just pulled out the OS disk and erased the hard drive. Thanks for the response though.
You could have maybe dealt with this in 'Safe Mode with Networking" but we will never know. Glad you are OK. Now make sure you update everything, including any parts of your system that you may not use, important to prevent vulnerabilities.