I have been using 2.5 and usually had no problem rendering avi and importing it into after effects with an alpha channel. Now all of a sudden my videos render with no alpha channel, am I doing something wrong?
Are you shure that it was an avi-file you rendered? The only common videoformat I know of, that can hold an alphachannel is Quicktime with animation codec and more than 16,7 Million colors . And there are ofcourse sequences of 32 bit images like tga or png.