AVG Interface has stopped working

Hello Dirk,
We regret for the inconvenience caused. We would request you to run AVG remover tool to completely remove AVG and then re install it.  
Please click this link http://aa-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.

I tried to reinstall, then a popup says "AVG product intallation MSI failed @AVGMSI_Error 1921"
Can someone please assist me?

Hello Dirk,
We regret for the inconvenience caused. We would request you to run AVG remover tool to completely remove AVG and then re install it.  
Please click this link http://aa-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.

Dirk, If applicable… For your info, just in case that you are unaware, you can post the screenshot here in your topic. Click on 'Answer' & then click on the 'Image' [mountain symbol] & follow the instructions. 
In future please refrain from carrying out multiple topic postings on the same subject! You won't obtain an answer to your query any faster!. 
AVG Guru