Hello;
Allow me to welcome you to the HP forums!
I read your post about wanting to recovery your PC to its original OS and wanted to help.
The Recovery Manager uses files that HP preloaded on the PC when they assembled it. That's why you can use it to recover the original OS and other stuff -- the files needed are stored in the Recovery partition.
After you Upgrade to Win10, you can NOT use the HP Recovery Manager successfully anymore -- for two reasons:
1) Corruption -- the Win10 Upgrade tool is known, in some cases, to corrupt the OEM Recovery information. When this happens, the files the Recover Manager needs have been erased or corrupted. Installing a fresh Recovery Manager does nothing to fix the corrupted files.
2) Missing information -- the Win10 Upgrade does NOT install the files the Recovery Manager needs to recover Win10. Installing a fresh Recovery Manager does NOT install those files.
In addition, the Win10 GoBack function is know to be unreliable and when it fails, it can leave machines in a corrupted state -- which doesn't always happen, but it does happen often enough to be a problem and you won't get any warning in advance that it is going to trash your PC! So, there is no way to go back to the former OS using Win10.
What will work is restoring your machine to its original factory condition using HP Recovery Media. This is a set of DVDs and a CD, or USB stick, that will erase the hard drive (removing all data, settings, and applications, reinstall the original OS, drivers, and some HP Utilities. In some cases, you may be able to order a USB stick instead of disks. You have to order these from HP; they can not be downloaded.
You can look online for Recovery Media starting with the linked paged: http://support.hp.com/us-en/drivers
Once there, input your Product name or number. On your Software and Drivers Download page, select your Operating System and and Version. Click "Update". If HP Recovery Media is available for your machine, down near the bottom of the page, you will see an entry for Order Recovery Media-CD/DVD/USB. Click the "+" symbol to expand that entty and click on Order Media for details.
Or, if you prefer, you can do the same by contacting HP Customer Service:
If you live in the US or Canada, contact information is on this page: http://www8.hp.com/us/en/contact-hp/phone-assist.html#section1
If you live elsewhere, contact information is on this page: http://www8.hp.com/us/en/contact-hp/ww-contact-us.html
NOTE: After you get through, stay on the line until you are finally able to talk to some one -- it can take a while!
Note that if HP no longer provides Recovery Media for your model, a couple of other sites you can check are: http://www.computersurgeons.com/ and http://www.restoredisks.com/
Be sure to read through the material in the linked thread BEFORE you attempt the recovery: http://support.hp.com/us-en/document/c00707939
Good Luck
I am a volunteer and I do not work for, nor do I represent, HP.
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