Its not likely your AVG blocking anything or you would be getting an alert of some kind. What is the extension of the file you are trying to play?
Its more likely you don't have the proper codec installed. Try downloading Gspot Codec Information Appliance
. This little program will tell you if the file is corrupted or which codecs you need to play it and which codecs you already have. Be careful downloading codecs cause they are rife with malware if you get them from the wrong place. If you find you need some further codecs then post back with the results from Gspot and we'll help you find some good ones that are safe to download.
If this is a link that you click to get the video your firewall may be blocking it. Check the permissions in your firewall. Go into the options or preferences of your media players and find the area about firewalls and set it up in there. Alternatively you can right click the link, click save as and save to your hard drive and play it from there.
When the only tool you own is a hammer, every problem begins to resemble a nail. Abraham Maslo
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