Adware/Virus can't be detected or removed!?

Hello AVG Community,
I noticed that on every website I visit that there are a lot of words in blue, capital letters and underlined. They all have links to websites like fake PC repair sites.

Sometimes on a random website I get an pop up box that tells me to scan my PC too and sometimes the adware/virus redirects me to suspicious websites when I click on a link. Also: When I click a link I often see that another website opens really fast but then it jumps to the website I wanted to visit. The name of the suspicious website that often opens and closes very fast is "csh.lt".

I'm very sure my PC is infected with Adware or some kind of virus.

I have AVG Ultimate 2015 Internet Security and ran two scans without any findings. I then downloaded Malwarebytes but it couldn't find any threats too. Then I changed the scan settings of AVG and checked the 'Tracking Cookie' box as well as all other available options.
AVG found a very dangerous Tracking Cookie this time.
I cleared the quarantine but when I went to check the blue words and Adware still appear on every website. Unfortunately I did not write down the name of the threat AVG found but it's name started with "Tracking Cookie…" and I believe it ended with "-sys". The threat was found in the Local/Temp folder.
I did 3 scans after this but AVG did not find anything even though the threat is still visible and clearly active.

I did not download any content this week besides a single picture yesterday. The threat appeared visible with the blue words etc. today for the first time.

Please help me to remove the adware/virus from my PC.
Thank you.

Hello Freddy,
We apologize for the inconvenience caused.
We understand how something like this will try your patience.
On seeing your description, we see that you have installed AVG Ultimate 2015 version.
We would request you to run AVG remover tool to completely remove AVG 2015 and then re install 2016 version and try to scan your system completely for threads. If issue still persist, please let us know.  
Please  click this link http://download.avg.com/filedir/util/AVG_Remover.exe to download and "Run" the AVG Remover tool.
1. Please select the AVG products which are shown in the remover tool window and then start removal process.
2. After the remover tool process is successfully finished, restart your computer.
3. After the restart,  manually delete the AVG Remover folder in the C drive of My computer.
To reinstall please follow the article http://avgclick.me/InstallUltimate .
Please feel free to get back to us for further assistance.
Thank you.

Hello Freddy,
We apologize for the inconvenience caused.
We understand how something like this will try your patience.
On seeing your description, we see that you have installed AVG Ultimate 2015 version.
We would request you to run AVG remover tool to completely remove AVG 2015 and then re install 2016 version and try to scan your system completely for threads. If issue still persist, please let us know.  
Please  click this link http://download.avg.com/filedir/util/AVG_Remover.exe to download and "Run" the AVG Remover tool.
1. Please select the AVG products which are shown in the remover tool window and then start removal process.
2. After the remover tool process is successfully finished, restart your computer.
3. After the restart,  manually delete the AVG Remover folder in the C drive of My computer.
To reinstall please follow the article http://avgclick.me/InstallUltimate .
Please feel free to get back to us for further assistance.
Thank you.