More spam
I received an email from AOL (not my service provider) returning an email which supposedly I had sent the day before. I deleted the message together with the unopened attachment. Whatever it was, it wasn't something I had sent. I am not using a spam filter because most of my emails are electronic circulars from the various societies to which I belong, and I might inadvertently block the mass mailings I currently welcome. Incidentally, I am one of your silver surfers, a woman in my 70s. Rosemary Naylor

Jack Schofield replies: People sending spam usually fake the addresses, and if they are selected at random, there is a chance that some spams will be sent under your name. If they are rejected or bounced, they will arrive in your in-box. There is not much you can do except delete them, as you very sensibly did. However, filters can reduce the burden by eliminating most junk mail. Many filters divert suspected spam into a separate folder so that you can make sure you are not losing anything you want. In some cases, you can add specific addresses to a "white list" to make sure mail is let through.

One caveat: if your PC is hacked, a spammer could run a mail server remotely on your machine. In that case, you would be sending or relaying spam from your unique IP (Internet Protocol) address, even though it would not appear in your own mail software. It is therefore wise to run a firewall such as Sygate Personal Firewall or Zone Alarm - both free for home users - and pay attention to things like traffic indicators (real or virtual blinking lights). This scenario may sound unlikely, but the problem has become so bad that America's federal trade commission has just launched a campaign about it. However, most victims are companies and educational institutions that have good broadband connections and unattended computers, not home users, and especially not home users with dial-up internet access.

Upgrade
I would like to update the 400MHz AMD processor in my IBM Aptiva, so I can move up from Windows 98 to Windows XP. John Whitehead

JS: The motherboard manual will tell you which processors it will support. If yours is a Slot 1 design, the fastest upgrade is likely to be a 433MHz Intel Celeron. Companies such as Evergreen Technologies supply faster chips to preserve old machines. However, even if you upgrade the processor, you will still have a PC with a slow bus, a slow graphics card, and not enough memory to run XP. (You don't mention that, but I'd guess you have 64MB and need at least 128MB.) You could, of course, buy a new motherboard, a new processor, and new memory, but I suspect it would be cheaper and easier just to buy a secondhand PC.

Add/Remove
One of my grandsons has left a lot of old games etc on the Add/Remove folder. Can you help me get rid of them? Does it mean that I have to go into the Registry, which frightens me? Bill Frost

JS: These obsolete entries are completely harmless, so you could simply ignore them. But yes, you can get rid of them by editing the Registry. Go to Start|Run and type regedit in the box. Go to: HKEY_LOCAL_MACHINE|SOFTWARE|Microsoft|Windows|CurrentVersion|Uninstall and delete any unwanted keys. You can probably avoid the manual process by using a free Microsoft utility called TweakUI, if you have it. If not, try Add/Remove Pro v2.08, which you can download free from http://superwin.com/freeware.htm.

Well Polished
Is there anywhere I can download a Polish character set for my iMac running OS X? There is no Polish listing in System preferences| International. Jo Duddy

JS: You need to install the Central European character set, and there is a paid-for version at www.fontmenu.com/site/_CE_Mac.html. However, if you install the OS 9 language kit then OS X will pick it up. See www.alanwood.net

Backchat

· Brian Kelsey asked about using the keyboard to control Windows, to minimise the use of a mouse. Chris Martin and Mike Swan both suggest using a Wacom tablet instead. "I switched to a Wacom Graphire 2 tablet pen and find it much more comfortable to use," writes Chris. "I would not consider going back to the rodent ever again!"

Oded Szpiro reminds us that some speech recognition packages allow a PC to be operated using spoken commands. Finally, I did not have space to mention Apple's version of Mouse Keys, which is part of the Easy Access extensions to Mac OS. For universal access features in Mac OS X (Unix), see www.apple.com/macosx.