Hi daughertyp (!
)
Will has almost certainly hit the nail on the head.
A look at this page
http://kb2.adobe.com/cps/407/kb407111.html reveals that for Canon T1i, you will need ACR 5.4 (or later).
You need to find a way to get ACR to open (if you have an older RAW file that'll do), then look in the top left corner, on the title bar, and it will say what version you have.
Then follow the link to the Camera Raw page;
http://www.adobe.com/products/photoshop/cameraraw.html and depending what software and computer you have, follow one of the four links to another page and so on.
If you have trouble, tell us what computer you have (Windows or Mac) and what Adobe product you have;
Lightroom 2.x, Photoshop
Elements 6/7/8 or
Photoshop CS 2/3/4. If you don't have one of these 7 versions, there could be a problem.
A first name would be nice, given your rather unusual username*
, thanks.
* I hope that isn't your name, or I will have 'put my foot in it' again
Good luck,