Doing a complete uninstall, removing registry entries and all

Hello Thomas,
We understand your concern. We appreciate your valuable effort in trying to fix the issue.
To remove the traces of AVG and then to install AVG Antivirus free we request you to run AVG remover tool. To run AVG remover tool follow the below steps :
Please click on the below link to download remover tool
http://aa-download.avg.com/filedir/util/AVG_Remover.exe
Accept the license agreement and then choose AVG Product and remove it.

A friend of mine called me, telling me that she only had 5 days left of her trial period of the Professional version, so I tried to unstall the product prior to installing the free product again from your homepage. A couple of times, a popup appeared, telling me that another uninstall was still in progress, so I rebooted her machine. After that, I was able to uninstall AVG. At least that was what I thought. I then installed AVG Free, but when I opened the dashboard, It still said that there were only 5 days left of her trial period.

How do I perform a total uninstall, removing registry entries and all, to come to a state where I can do the installation again?

Hello Thomas,
We understand your concern. We appreciate your valuable effort in trying to fix the issue.
To remove the traces of AVG and then to install AVG Antivirus free we request you to run AVG remover tool. To run AVG remover tool follow the below steps :
Please click on the below link to download remover tool
http://aa-download.avg.com/filedir/util/AVG_Remover.exe
Accept the license agreement and then choose AVG Product and remove it.

Hello Thomas,
Thank you for your kind post and for your support of AVG products. That's great to hear your issue has been resolved now. If you are facing any further issues with AVG program please let us know and we are happy to assist you.
Thank you.

By following your procedure, the matter has now been resolved. Thank you very much for your kind assistance.

/Thomas

NOTE: Once the AVG Remover Tool has done with its process. Please go to the drive where you installed this tool and look for a folder named as "AVG Remover" and I request you to delete it manually.
To install AVG Antivirus Free 2016 we request you to use the offline installation. To determine whether your OS is a 32-bit or 64-bit, please click on this link. http://support.microsoft.com/en-us/kb/827218
For 32 Bit : http://files-download.avg.com/inst/mp/AVG_Antivirus_Free_x86_694.exe
For 64 Bit : http://files-download.avg.com/inst/mp/AVG_Antivirus_Free_x64_693.exe
Feel free to contact us for any further assistance. Thank you.