Per PogoPlug Customer Support, "Please note that the .avi media files are not supported on Pogoplug".  I am very confused by this because I have shared an AVI file found on my PP enabled device and there were no issues.  Last night I tried to share a file from my desktop NOT a pogoplug device and the person I shared it with was not able to play the file, however they could download the file.  When I queried further with PP support on this behavior they responded, 

"Be it either Pogoplug device or computer installed with Pogoplug software, transcoding of files should take place according to 'Media Settings' configuration at the webUI (webUI ==> Settings ==> Media Settings)".

"However, you should expect this to act this way only for supported media file types, which is not the case regarding .avi in particular".

I guess it is time for me to give up on PogoPlug as it should not be this difficult to share a file yet alone an AVI file, however it would be nice if I could find someone knowledeable on the PP software specifically AVI files so I can be fully informed prior to moving onto some other product.