Recently updated my Windows 10 to version 1709, so initially thought the strange problems were due to that. However, after running sfc /scannow and DISM /Restorehealth commands, it appears my computer may be infected.
Here's what happened after upgrading to Windows 10 version 1709: I am home sick with the flu and not up up to doing much, so have limited myself to re-visiting some old computer game related websites. However, some of the websites were not active any more, and a couple websites gave me warnings my computer was infected and to download some software. I exed out of those websites rather than downloading anything, and thought I was safe.
However, my computer has gradually been acting up ever since. The first thing I noticed was that I could no longer right-click on icons in the taskbar to open a second copy of a program, such as windows explorer. Then I noticed the Windows Start button would no longer open, so I could not access Windows Defender to run it. Finally, i noticed some strange, new folders were appearing on my C: drive, containing a mixture of strangely named files in multiple formats (txt, jpg, pem, mdb, sql, doc, rtf, docx, xls and xlsx).
I ran the following manual scanners today, but they did not find anything: Emisoft antimalware, Superantispyware, Malwarebytes Antirootkit, Zemana Antimalware and Malwarebytes Antimalware. (Was not able to access Windows Defender, so could not run that one.)
I also tried running the ESET online virus scanner, but after waiting 3 hours it was still running (and had found no viruses) so I quit it.
Please help. I am still sick with the flu, and now apparently have a sick computer.