How to Fix AVG 500 Internal Error 421?

AVG antivirus is the strong antivirus which secures your device from external threat. This, unwanted AVG 500 Internal error 421 can occur anytime. You can install this trusted antivirus through This software monitors the network traffic and creates a line of defense between your device and threat. In this article, you will read the causes and solution of AVG 500 Internal error 421. This error occurs when you shut down or start up your computer. This error also slows down your computer system.

read here also>>> Step By Step Guide To Fix AVG Error Code 0xe001f958:

The Causes of This Error:

The causes of the AVG 500 Internal Error 421 are if there are infected AVG antivirus files with malware or viruses, incomplete download or installation of AVG antivirus, other software might have deleted some files of AVG mistakenly, and this antivirus changes corrupted windows.

Ways to Fix AVG 500 Internal error 421:

  1. Scan for viruses:

The reason of this error may be virus or malware in your device. In this situation, you should run a thorough scan for malware. After this, you should check that the problem still persists or not.

  1. Cleaning the system junk:

You should regularly clean the system junk files. For this, first you have to click on the “start” button. Then, you have to type the “command” in the search box. After this, you have to press and hold “Ctrl+Shift” keys on your keyboard and then just tap on “enter” key. Here you will see the dialogue box in which you type “cleanmgr” in that box. Then you have to press Enter key. Now, you will see the Disk Cleanup starts calculate the space. In the dialog box, you have to mark the “temporary files” category. At the end, you have to click on the “ok” button.

  1. Repairing registry entry:

For repairing registry entry, you have to click start. Then you have to enter the “command” in the popped up box. Here the dialog box will prompt and you have to click on “yes” option. Now you will see the Black box windows. Here you have to type “Regedit” and then press “enter” key. Now you have to select the key related to error 421. After this, just choose “export” from the file menu. Just type the name for your backed-up file. Now there is an “export range” box, you have to select “Selected branch” from that box. And you will get a .reg file after saving it. Now successfully you your backup of your AVG related registry entry.

  1. Installing Windows Updates:

For this, first you have to click on “start” button. Then you have to go to the search box and then you have to type “Update” and press Enter key. Here you will see the dialogue box of windows update. If you see the updates are available. At last, you have to click on Install updates.

  1. Installing Windows again:

If you again face the error then you have to install the windows again.

This method will solve the AVG 500 Internal Error 421. If you are still facing the error then you can call the customer care executive anytime on their toll free number. For detail information, you can visit to the site of AVG through