Trackball not working at startup

Dell XPS8930 with Win10 Home, Ver. 21H2 (OS Build 19044.1348) -- Due to an injury, I use an old MicroSpeed trackball, which requires a serial-to-USB cable (PL2303 driver). For a week now, the cursor is not visible at startup. I have to have my mother pull the USB end from the back of the PC and plug it back in, and it works fine. I've tried a different USB port, and reinstalled driver for the cable and trackball. A new USB trackball of the type I can use is $150. I'm at a loss what to try next. Ideas?

Samuria said:

Welcome to the forum. Has it ever worked? How is usb set in the bios it may need lecacey mode set or it may be the adapter often they arnt that good

Everything has worked fine for years. No new hardware/software except the usual Win10 updates. Except for replacing a hard drive many, many years ago on another PC, I don't get into the BIOS or other settings, so I'm a super-amateur. My PC boots fast; I tried F2 twice and both times the screen stayed black and nothing happened. I turned the PC off/on again and the track ball works, but only for that one session. Next reboot, no trackball. I also tried a 2nd way to bring up the BIOS, as described in this site, but same result.
https://www.hp.com/us-en/shop/tech-t...up-windows-pcs

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I added a regular USB mouse so I can look around when the trackball isn't working. If I tweak something on the Com port settings, like the checkbox shown here, I hear the tone like plugging in the adapter and the trackball starts working. It's as if it needs something after startup to wake it up.


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And the solution was... In Device Mgr, uninstall the serial adapter under "Ports (COM & LPT)". Reboot.