PC hardware forum: "Out of Scan Range" monitor message

I have a Dell Insperon Notebook, that Ive attached an external monitor (Gateway Vivitron 20), keyboard and mouse (both dell) to. (Through the ports in the back, not with a port replicator) They all have worked very well for almost a year now. Then just the other day, my monitor lost the primary color of red and a few hours later it just sat there with a black screen and a blue box that has a message in it that reads out of scan range.

I restarted my computer several times, checked both power cord & connector cord for any kind of damage, I also check to make sure they were properly attached to the back of the monitor and the power outlet or computer. I even shut the whole thing down let them sit for a day. I have done some searching online, I found one article regarding an out of scan range message that hinted at the problem being the monitor is to old for the computer it is hooked up to. Most of the article was very technical and I couldnt understand much of it.

Now I know loosing a primary color can be any number of problems but what confuses me is the out of scan range message, if its because the monitor is to old for the computer its hooked up to, why did it work for almost a year with no problems. Is my monitor in need of some major repair or is there a problem with my computer reading the monitor. Any help anyone can provide would be greatly appreciated and thank you for you time in advance.

By the way, when I first hooked up the monitor to my laptop, I did not have to install a driver, it recognized the monitor right away and worked fine. I just plugged and played