Can i hook up my Canon Rebel XTI EOS to my Quatum Qflash Model T2

Try here:
http://thydzik.com/downloads/canon-service-manual-eos-kiss-digital-x-eos-digital-rebel-xti-eos-400d-digital.pdf

or other links/ideas maybe here:

http://thydzik.com/canon-service-manual-for-eos-kiss-digital-x-eos-digital-rebel-xti-eos-400d-digital/

It is not possible to use the Nikon SB-50DX directly on a Canon EOS Rebel camera. The Nikon flash gun hot shoe contacts do not match the Canon hot shoe contacts.
You can use the Nikon as a slave flash gun with a PC flash cord that matches the Nikon's flash contacts then connect the end of this flash cord to a flash trigger. The Canon's flash can then trigger the Nikon flash gun via the flash trigger.

Flash ready light on , but dont fire, xenon tube need replacement .

HI,
The Canon Rebel T2i was announced on Feb 08, 2010 and Canon just started shipping the DSLR. Your salesperson was thus correct.
The DSLR is also known as EOS 550D. It differs from the previously model by:

Higher resolution 18MP CMOS with gapless micro lenses

ISO 6400 no longer in 'expanded' range (12,800 max remains the same)

Redesigned buttons and new movie/live view button

Customizable auto ISO ranges

Improved 63 zone metering (iFCL)

3:2 format screen with more pixels

Improved movie functionality

Slightly higher burst shooting rate (though buffer holds fewer shots)

HDMI control (CEC)

SDHX Compatible

Manuals for the camera and all software supplied is here:

http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=314&modelid=14256

The manual for the camera itself is the last one listed, titled:
"EOS DIGITAL REBEL XTi / EOS 400D DIGITAL Instruction Manual "

You will have to go into the setup menu and set it up for hotshoe, instead of cord or IR.

Vista is your problem. Solution...buy an inexpensive card reader to download your pics to a folder you create on your desktop. From there, you can send the pics to your photo editing software.

Here's how to do it:

Go to this page: Canon Digital Rebel XTi

Click Drivers & Downloads, scroll all the way to the bottom, and click on the PDF link as shown.

EOS DIGITAL REBEL XTi / EOS 400D
DIGITAL Instruction Manual
EOSDRXTi400DIM-EN.pdf

EOS 400D / Rebel XTi Digital Camera
EOS 400D/Rebel XTi doesn't have live view function, so you cannot see the picture you are taking.

if it is an auto focus lens that works on one eos camera, it should work on almost all of them. the only known exception is that some high end extenders will not fit the eos1dmarkII as it protrudes into the opening too far.
but a good rule is that if it fits without any obstruction issues, it should work. try cleaning contacts on the lens and camera body. if that doesn't fix it, talk to Tamron. you can use it manually, but will not be as easy and you would get less predictable results.

my suggestion is to always go with lens from camera maker.

sounds like there is an issue with the tamron lens. not the camera.
good luck
mark