PC's alwasy came with either recovery disks, or a recovery partition to boot from, or the option to make the recovery disks yourself. Once you found out how (user manual, HP's site, HP tech support), use them to go back to factory settings. Maybe you can still order those disks with HP Customer Service. That's cheaper than buying Windows 7 or 10 yourself, but more expensive then installing Linux in stead of Windows.
It's all your choice.
Then when you have it running again consider making an image backup (Easeys Todo is free, it can be done free from Linux; Acronis isn't free) so you can always go back to the latest backup of your full system.
Happy Boxing Day... At least, I hope yours has been better than mine! I'm running Windows 7 and have encountered the most problematic Windows 7 issue. I'm assuming this is a virus problem - but I am not an expert. Can anyone help?
The symptoms are as follows:
1) I can't install any new programs. When I try to run any new new program associated with scanning, antivirus, or other fix-it tools, the 'User Account Control' popup asks me if I want the program to make changes to my computer. When I click the 'yes' button, the screen goes semi-dark and I have to press ctrl-alt-del to cancel. The 'User Account Control' popup-box has a link, bottom-right, that offers to let me "change when these notifications appear", but clicking on the link has no effect.
2) I can't uninstall any programs either. Control Panel tells me to "wait until the current program is finished uninstalling or being changed" (which it never does).
3) I cannot start Windows in any of the Safe modes; when I try that, it hangs on the 'Welcome' screen.
4) I often cannot shut down or restart the computer normally; it hangs - or takes ages lingering on the 'shutting down' screen, and I sometimes have to hold the power button down to shut everything down, rather than waiting indefinitely.
Remedial steps attempted:
1) I ran AVG free antivirus. All it found was some PUPs. It removed them; there was no change.
2) I ran MS Security Essentials scan. It found one "dangerous virus" called Onaha.A ...The program quarantined it, but the symptoms remain. It was unable to uninstall the offending freeware program.
3) I ran SuperAntiSpyware. It found nothing.
4) I tried running Malware Bytes, but it won't open (like a lot of my programs: the screen goes semi-dark as soon as I try to run them and I have to press ctrl-alt-del)
5) I ran Hirem's rescue CD and one of the antivirus programs found and deleted 3 trojans, but the symptoms remain. Most of the anti-malware programs on the CD don't run. They may be out of date.
6) I tried restoring Windows to the only previous restore point (one day old) but there was no change. I thought I had other restore points but it seems not. I may have used third-party programs to save backup points had no longer have the programs on my system.
I'm assuming this is a malware problem, but I'll leave it to the experts to confirm. Diagnostics found no faults with my HDD or memory.
I'd love to run some other scans, but my computer won't currently run any diagnostic programs, and doesn't let run anything from a command prompt as administrator either. I do not have a windows 7 disc image to revert to, and I don't have the Windows 7 installation CD. (One was not supplied with this HP Compaq desktop PC, which I purchased about 5 years ago).
Thank you kindly for any help!