It could be that your restore points are corrupted.
Have you turned off system restore?
Turn off system restore. This will delete all of your restore points.
http
/windows.microsoft.com/en-us/windows/turn-system-restore-on-off#1TC=windows-7
Download C-Cleaner.
Free version works fine.
http
/www.piriform.com/promo/ccleaner-100314?gclid=CLCr1OvuoskCFYkBaQod6AcJUQ
Install it. This will remove left over registry traces of viruses.
Install Malware Bytes.
Free trial version is here.
https

/www.malwarebytes.org/mwb-download/
After you turn off system restore Reboot the computer. This step is important.
Uninstall Chrome, Every version as it can sometimes have 3 or 4 different versions installed at once. When you upgrade the old versions are still on your hard drive. Chrome should be classified as spyware as it tracks everything you do and reports it to Google.
Start ---Control Panel---Programs and Features. In win8 -8.1 click on the Control Panel Tile.
Click on Chrome and click Uninstall at the top of the page.
After rebooting Run Malware bytes. You may need to reboot again to finish cleaning.
After finishing with MalwareBytes(after reboot if required) Run CCleaner.
This will delete temp files ,temporary internet files etc...
Next step.
Click on the registry Icon on the left hand side. Click "Scan For Issues"
This will check for invalid registry entries.
Once the scan is complete it will ask if you want to make a backup uf the registry issues it detected. Click "NO" If you save them and install Chrome again it will search the hard drive for previous chrome registry entries and restore them. We do not want that to happen as it will reinfect you.
In the windo that pops up click " Fix all issues"
Repeat the above registry cleaning steps until no more errors are found.
Last step.
Follow the instructions found on this page to completely remove Omnibox.
https

/malwaretips.com/blogs/remove-omniboxes-virus/
Follow ALL steps and reboot when needed. DO not SKIP steps or skip Rebooting ,It will not work completely.
Once you have finished the cleaning process Run CCleaner again on the registry cleaner. It will find a few more bad registry entries after Omnibox is removed. Do not save registry settings again. Click Fix all again and rerun until it finds no more errors.
Turn system restore back on and reboot.
And last of all Omnibox comes preinstall with a lot of free downloads. Be careful of what you download and install or you will get infected again and again anD again if you keep on downloading and installing free stuff. Most free downloads come with a price. It install lots of tracking, Redirecting, Adware crap on your computer. That is why it is free, so you will download it and install all of the other crapware that comes with it.
All of the software I linked to perfectly safe, some do have annoying pop ups when you run it asking you to buy the paid version, but only when you run it.And will clean and remove crap whether you have the free or paid version. The paid version does not have the popups.
If you are always downloading free junk you may want to use the paid version of Malware bytes, as it is the best antivirus/cleaner you can get.
And will stop a lot of the crap from installing to begin with.