Hi Jack
Thanks a lot for your response. The URLs you mentioned are indeed very good source of help for combustion users. But unfortunately it couldn't solve my problem.
But then I tried again myself and opened all the avi clips which I was able to see in combustion and which I was not, in Premiere and studied the properties. All the files that I am unable to see in combustion were shown in Premier as having 8 bit depth and all the clips which had no problem are 16 bit depth( though all these clips were shown in combustion as 24 bit).I changed the bit depth of composition in output setting in combustion to different bit depths but of no use. I don't know the reason but at least I now know which kind of files to use in combustion. I am using Combustion 2. Can any one please through some light on this mystery please?
Thanks again for your response.
Zeni