Most people don’t realize that everything that appears on your screen is not always put there by your computer. Because the mouse pointer disappears when you move it beneath the flag, the monitor itself probably put what you're seeing there.
I, too, have encountered the occasional odd message on my monitor.
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Monitor problems
Considering what you’ve just described, I believe:
- Your monitor is faulty; it’s having some kind of a problem.
- That random string of characters that you are seeing at the top is a diagnostic code or potentially even just an error of some sort being produced by the monitor itself.
These days, most monitors (especially the LCD ones) are powered by small micro-computers themselves. It's not necessarily a Windows-compatible kind of processor, but a little processor runs software that actually does all of the things that the monitor is supposed to do. It’s the thing that handles the contrast and the brightness when you adjust those settings and probably does some interpretation of the signals that come in over the connection to the monitor.
But once you start throwing a processor in there, then it has the ability to do diagnostics and report issues when they occur. That sounds like what's happening in your case.
Diagnosing the monitor
One of the easiest way to rule this out, of course, is to plug in another monitor. Borrow one from a friend or a store (if they’ll loan you one for awhile). If that problem goes away when you replace the monitor, then it’s probably the monitor that's at fault.
Like I said, monitors are smart devices, and of course they too can fail.
Before giving up on it, I would have you check the manual for your monitor. If you don’t have it, you may be able to find it online at the various manufacturers’ websites. The manual itself may have information about these specific images or messages that appear on your screen and what they mean.
