Firewall Blocks All Access to Thecus NAS Drive

Hi Chris,
We apologize for the inconvenience caused to you.Let's work together to fix the issue. please follow the below steps to fix the issue.
Please open AVG->Click on Internet Security part->Go to menu->settings->components->Click on Customize option in firewall->go to network profile->change the connection to private.
After this process, If you need any further assistance, please feel free to contact us. We are always here to help you with your issue.
Thank you.

Hello Chris,

We appreciate your efforts. From what we have learned about your issue, we would like to offer you a free remote assistance service as a best way of resolving it. We have sent an email instructions to connect with our remote technician. Please follow the instructions from the email.

Thank you.

The latest update appears to have blocked all access from my Windows 7 machines to the Thecus NAS Drive. The NAS is on a fixed IP, and when the firewall is active it does not even respond to PINGs and certainly does not allow Windows to map to it for shares.
I have tried to add a packet rule allowing ALL traffic to and from the IP address for the NAS, but this doesn't appear to help.
This does not appear to be an issue on other machines on our home network which tend to be running Windows 10.

Hi Chris,
We apologize for the inconvenience caused to you.Let's work together to fix the issue. please follow the below steps to fix the issue.
Please open AVG->Click on Internet Security part->Go to menu->settings->components->Click on Customize option in firewall->go to network profile->change the connection to private.
After this process, If you need any further assistance, please feel free to contact us. We are always here to help you with your issue.
Thank you.

OK, did as you suggested and it is partially successfuly. It does indeed make the NAS drive available but then intermittantly the connectivity to the NAS drive is subsequently lost for no obvious reason. For example, if editing a Word document located on a NAS share, during the editing session connectivity may break and then resume periodically.
This is new behaviour since the update for AVG came down last night.

If I switch the firewall off, connectivity is available and reliable, with editing of documents located on the NAS being achieved with no interruptions or problems.  As you can see from the screen capture below, the network is configured as PRIVATE as per your direction.
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