Q I am having trouble updating my anti-virus program online even though I have a working internet connection. What can I do to fix this?

NE from Bristol

A It sounds as if your computer has already been compromised by a virus that is now stopping you from upgrading your protective software. One way it can do this is by covertly blocking your browser from accessing certain anti-virus update websites.

Try installing a different web browser, such as Opera (www.opera.com) or Firefox (www.firefox.com), to see if that fixes the problem. Another option is to download a new anti-virus program, such as Malwarebytes’Anti-Malware (free from tinyurl.com/594vr7), and run a scan with it.

If neither option works, you should seek professional advice. You may even have to reinstall Windows.

Q I am trying to clean up my computer, and I’d like to know if there is any free software that will identify the largest files on my hard drive?

TH from Warwickshire

A My favourite program for this task is Treesize Free, which is free from tinyurl.com/28pls. Once you have installed the software, you tell it to run a scan, at which it skips through your hard disk, identifying which folders and programs are hogging all the space. It’s a superb tool for locating large chunks of data that you may have forgotten about, such as old video clips. I’m sure you’ll be surprised with the results.

Q Whenever we shut down our PC we get a window saying “end program sprtcmd.exe”, at which the shutdown process pauses. How can we stop this happening?

JA from Surrey

A I’ve had several e-mails on this subject. This program is an automated support utility used by Dell Computers, and you are a victim of its latest software update, which appears to have broken the Windows shutdown process. The best way to stop this is to bring up the Task Manager (by pressing the ctrl, alt and del keys simultaneously), then click on the Processes tab. Find the application called “sprtcmd.exe” and click on the End Process button at the bottom of the box.

Once you have done this, go to Windows Control Panel, select Add/Remove programs, then remove the Dell Support Center program from your computer. That should clear it up once and for all.

dontpanic@sunday-times.co.uk

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