Well, I had the same problem(s) 2 years ago. Here is what I did and have had nothing but good times since.
1. Make a list of all "user names" and "Passwords"
Note: If your browser is Mozilla FireFox, it's all taken care of in "Tools", "Options", "Security".
The list in hand is very comforting, ha.
2. Download "CCleaner"
http://www.piriform.com/ccleaner/download?upgrade first time is free.
Note: The nickname for this is "crap cleaner" and the crap is there ! It can't hide from this one.
This is not an "Auto Running" program. Usually, a once a year run may be needed.
3. After that is done and you've rebooted your computer, "Run" a complete "Defragmentation " of the main hard drive and reboot again.
4. Download " Malwarebytes"
https://www.malwarebytes.org/lp/lp4/02_r/?gclid=CKPZpKqo_cECFZFhfgode10AIA Note: The free one is just fine. This program "Handles" stuff as it tries to get into your computer.
If a long list of stuff in "Captured" another complete defrag and reboot is best.
This will aid most any PC.
It is amazing how much "stuff" is/was messing with almost everything you tried before .
Now, if we have our Iceshanty server tech grab his hammer and .........
Please respond here if you like.