I am most at issue with .avi files. I was able to play a certain one a few days ago - but now (using Windows Media Player 10) the line turns orange and has an exclamation point beside it. This happens to a lot of mpg files sometimes too.

I have read to use Gspot to determine if it's a missing codec, but I can't figure out how to test the particular movie that wouldn't play. I also read that I should download K-Lite codec pack. (But it requires a purchase)

What do I do?

Assuming that you have XP SP2 I would recommend WMP 11 which is final now:

http://www.microsoft.com/windows/win...1/default.aspx

I also do use K-Lite and it works well. Just do the Custom setup and check the file associations carefully or it will override WMP. This can also always be restored by using: Set Programs Access and Defaults.

Free:

http://www.free-codecs.com/download/...Codec_Pack.htm

or if u can't fix ur problem,
u might need converter
here is free one.
http://www.freedownloadscenter.com/M...Converter.html