What KIND of video... ie what CODEC is that file?
This is aimed at Premiere Pro, but may help
A link with many ideas about computer setup http://forums.adobe.com/thread/436215?tstart=0
Many of the ideas at the next link are generic enough they have helped some Non-Premiere users fix problems
Work through all of the steps (ideas) listed at http://ppro.wikia.com/wiki/Troubleshooting
If your problem isn't fixed after you follow all of the steps, report back with the DETAILS asked for in the questions at the end of the troubleshooting link
I have only experienced similar, when converting DivX files to DV-AVI Type II for editing. However, that Duration problem is ONLY in PrPro, and I actually use PrElements to correct whatever is wrong. PrE will see the correct Duration, and I just turn right around and Export/Share to the same exact format/CODEC - those work perfectly in PrPro. In my case, PrE gets things right! Similar, but obviously different than your instance.
Now, as John asks, can you tell us more about your files?
The great, free utility, G-SPOT will give you the full details, including the Duration and also the CODEC used. It would probably be easiest to just post a screen-cap of G-Spot, with that file in it. That will save you a lot of writing.
It is a .MPG file. I have been downloading them for a year now with no
problem. I will go to the link you supplied and see if I can fix it. Thanks
Please let us know the specs. of this MPEG file. As with AVI, MPEG is but a wrapper, and much can be inside those. This ARTICLE will give you some background on "wrappers."
There is likely something to be revealed by G-Spot, that will point out why this is happening.