I have this all the time too (files offline). The reason is I use two PCs to work on my projects and I always store these on an external 3ooGB drive.
One PC sees this as the H:\ and the other see it as the L:\
So – I very carefully make sure that I tell the project where the missing avi files are stored once it opens. It repeats the request for other types of files (wavs, JPGs etc) as I have my files organised into folders by file type.
You can if you want kinda avoid this….but be wary as the plot may thicken somewhat…
If you know that Premier is expecting to see your files on say an L:\ and you know that they are located say on d:\data\myfiles you can ‘trick’ your PC into thinking that it has an L:\ by opening up a command prompt and typing…
subst L: D:\data\myfiles
Your PC will then accept that it has an L:\ and will look in d:\data\myfiles whenever L:\ is referenced!
As I said >>>>> not for the faint hearted!!!
Good luck!
Great forum guys.