Problem on a Program uploading.

i have an ardunio uno that have been purchase a week before but after the installation of the software when i connect the uno to the pc it doesn't blink the yellow the light stays steady......

kindly help me out from the problem

The ON led should be on. The L led usually flashes at 1 Hz; that is the factory loaded blink sketch.

When you power the board on, does the L led give a few quick flashes first before the blinking pattern? If not, there is no boot loader installed on the board. You can install (burn) it yourself but it requires a programmer or second Arduino; if you don't have the option to burn it yourself, I would return the board.

If you bought a clone, you might have to install the driver; often the CH340. Try to decipher the chip closest to the usb connector. An original Arduino will have 16U2 written on it.

Is the board recognised by your PC (Windows device manager or the Linux/Mac equivalents)?
Which operating system?
Which version of the IDE.
Is your board an original or clone? You can post a link to where you bought it, we might be able to tell you.

Please post the complete error message that you get when upload fails.