Your post is somewhat confusing, with the 2 antiviruses mentioned and the past tense for the error.
Anyway, in https://support.avg.com/answers?id=906b0000000bnNIAAY I read a possible answer:
"We apologize for the inconvenience caused.
We understand how something like this will try your patience.
Mostly this error is occur due to another Antivirus program or previously installed AVG on your system.
We kindly request you to please uninstall all other Antivirus program and try to install AVG free, so that we assure that your issue will get resolved.
Thank you."
So maybe the situation is confusing not only for me, but also for the AVG software.
If the above solution doesn't help, or doesn't apply, have a look at https://www.google.com/search?q=AVG+0xC0070643 for other suggestions.
I am new user of Panda Antivirus and i used to get Error Code 0xC0070643 during AVG Setup.Please tell me the solution for this error code.
All suggestions are welcome to this question.
Thanks in advance.

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