Why does my Dell Inspiron All-in-One boot up in 4 windows instead of 1

(1) Do you mean different screens as if you had 4 small separate monitors in that one screen? (2) Or 4 different programs open upon startup?

(1) If it is the first issue, check to make sure you don't have any screen splitting software in use. Look in windows display settings (Right click on desktop and select display settings) and disable all but one monitor, then set that monitor to max resolution. Find the program that is splitting the screen and uninstall it or turn it off.

(2) If is the second scenario, this is normal. When the computer boots up, installed programs need to start up. Some programs do it beneath the surface, so you never know, while others do it on top. You can just close these once they're done.

If this doesn't solve your issue, you'll need to attach some screen screenshots to show us what you mean. You can use Windows Key+PrtScrn to take a screenshot, and use this guide to post it: 기존 질문에 이미지 추가하기

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