Another possibility is the lack of quick keys. The DMA scanners won't do too much without setting them up. This is a subject that trips up many newcomers
It would be helpful to know what system(s) you are programming. Go up to the blue toolbar under the site title on the left, float your mouse over Database
then select Frequency Database
. Use the various pulldowns and selections to get to your state, then your system. C'mon back with the results.
We have a fairly decent wiki article which helps get your feet off the ground with DMA programming, including links to the Easier to Read manuals (don't try to use the Uniden stuff - use that as scrap paper...). DMA programming is not as straightforward as you might think - it takes some thought and planning to do properly.
Here's the article link - note that both here and in our wiki, anything blue is alink...
Program your DMA Scanner - The RadioReference Wiki