Q: I have a Dell Optiplex 990 desktop computer running Windows 10 with two monitors and a wired mouse and keyboard. Although our house has wireless and we run another laptop and two HP printers via wireless, the Dell tower is connected with an Ethernet cable, as it sits on my desk and the wireless router is right below the desk.

The Start button in the bottom left-hand corner of each monitor screen stopped functioning last week. Left-clicking no longer pops up the menu screen with tiles of functions and the left-hand column of programs and other functions. (This does still work on the laptop downstairs.)

I have searched on the internet for solutions to this “dead Windows button” issue but the suggested fixes run the gamut from the ridiculous to the sublime. Rebooting does not help, and Windows Update has been run several times without help. Troubleshooters also have not helped. We have Kaspersky virus protection and a full scan turned up no issues.

— Kirk Lamb

A: The first thing I’d try is to restart Windows Explorer, which actually controls the Start button.

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To do that, right-click in the System Tray at the bottom of the screen and launch Task Manager. Click on the Processes tab and then scroll down until you see Windows Explorer. Highlight it and then click on the Restart button at the bottom of the window.


If that doesn’t solve the problem, I suggest using Windows System File Checker to scan for problems. First, open the Windows Command Prompt. If you can’t access it through the Start button you can search in File Explorer for “command prompt.” Right-click on it and select “Run as administrator.”

When the prompt appears, type “sfc /scannow” then hit Enter.

System File Checker will scan for problems and replace any corrupt or missing files. The scan may take a while. If System File Checker makes any changes you’ll want to reboot your computer.

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Q: Is there any way to figure out what is causing an alert sound on my PC? I am running Windows 10, and my computer frequently makes an alert sound. (Sometimes it sounds 5-10 times in a row over a few seconds.) It is the same noise it makes when something is plugged into or (much less frequently) removed from a USB slot. It is also slowing the machine down, freezing it for a second or so every time. This started a couple of months ago and is getting more frequent.

I have sequentially unplugged everything connected to the machine one at a time to try to isolate this, and it continues no matter what is plugged in. I have updated Windows and every app on the machine. I have up-to-date malware protection running. Any ideas?

— Dave Lundry, Kirkland

A: No pun intended but it sounds like you need to take a look at the Event Viewer. You’ll find it by clicking on the Start button and then scrolling down to Windows Administrative Tools.


The Event Viewer keeps running logs of many kinds of events that take place under your computer’s hood — from programs accessing your USB ports to domain name server (DNS) errors over the internet.

The problem for most users, including me, is that it can be difficult to make sense of just what the Event Viewer is reporting. For example, at 8:19:40 this morning my system log in Event Viewer reported that: “The application-specific permission settings do not grant Local Activation permission for the COM Server application with CLSID {2593F8B9-4EAF-457C-B68A-50F6B8EA6B54} and APPID {15C20B67-12E7-4BB6-92BB-7AFF07997402} to the user PATRICKSURFACEB\pgmar SID (S-1-5-21-3313817969-2514332478-2302696435-1001) from address LocalHost (Using LRPC) running in the application container Unavailable SID (Unavailable).”


But since the logs are time-stamped, if you check for the exact time you heard those sounds you might find a clue as to what’s going on. And if you can’t make heads or tails of what you see, a technician probably can.