Some joker has sent me a virus attachment using UnknownSender@UnknownDomain as the email address. Can I trace it?
Matt Norman

Jack Schofield: Email addresses are easy to fake, but each email passes through several servers and most, or all, add a record to the header. Finding the sender is therefore a matter of reading headers, which means you can use the tools and techniques already developed for finding spammers.

There is a good introductory guide at www.arachnoid.com. SpamCop offers a service to parse headers and report spam, and there is at least one website (3dmail) where you can paste in a header for parsing. The aim is to find the sender's internet (IP) address. The ISP (Internet Service Provider) who assigned that IP can then identify the account used, and who owns it. See email.about.com/cs/spamtracking/.

Many Outlook Express users are not aware of the headers that are included with every email message because the software hides them. To see the header, right-click on a message and select Properties. Clicking the tab marked Details will show the header, and clicking the button marked Message Source will show the full message exactly as it arrived.

StartUp here

I have a PC and a laptop, and both have about a dozen programs on the StartUp list. Most of us don't know which are necessary. Can you recommend a reference?
Richard Rosser
richard@rosser.f9.co.uk

JS: Pacman, otherwise known as Paul Collins, has a comprehensive list. Since this is very long, you may want to start at pacs.portal.co.uk.

Configure it

In System Fix, you tell us to use msconfig to deal with StartUp programs, but Windows 95 does not have an msconfig program. How are we supposed to proceed if we have a similar problem?
Paul Hartmann
www.guycroft.clara.net/misc/sundries

JS: Windows 95 has a simpler program called sysedit, which lets you edit the configuration files. However, PC Magazine's Startup Cop is probably a better bet. You can download it free from download.cnet.com. A more powerful commercial alternative is Shensoft's Power Launcher Plus, a suite of mini-apps.

Missing input

When I start my PC, I see an automatic error message saying that DINPUT.DLL cannot be found. It does not appear to be causing problems except that my daughter's game, The Sims, no longer works.
Mike Ambrose
London W4

JS: The error message refers to the direct input part of Microsoft's DirectX code, used for playing games. Re-installing The Sims should re-install DirectX, or you can download the latest version from Microsoft.

Folder lock

On the Jonathan Creek episode transmitted by the BBC on Boxing Day, a laptop was discovered with a Windows folder that could only be opened with the correct password. Is it possible to do this on a standalone machine?
David Bradford

JS: I missed it, but Encryption Plus Folders Freeware will password protect folders. You can download a copy from www.pcguardian.co.com. There is also Magic Folders, which is shareware and therefore costs money to register. Mac users can hide folders with Freeguard, which is not very sophisticated, but free. For stronger alternatives, see download.cnet.com.

Hear this

My boss is dyslexic and finds using the keyboard difficult. Could you recommend the best of the programs that enable the user to speak to the computer rather than type?
Pat Roe

JS: Successful voice recognition has less to do with the software chosen than with the application and the user's motivation. All the programs work best when the application has a fairly restricted vocabulary and the user is highly motivated. A dentist or pathologist could be a good bet (probably can't touch-type uses the same terms all the time needs his hands for something else) journalists and secretaries tend to be a bad bet (can type quickly use wide vocabularies not motivated unless they get RSI).

The main options for PC users are Dragon Dictate and L&H Voice Express, both now owned by ScanSoft, and IBM's Via Voice Pro. Dragon Naturally Speaking Mobile comes (or came) with a Voice It handheld digital recorder that can send files to the PC software. This is a good approach for someone who wants minimal contact with the computer. For other compatible recording devices, see www.lhsl.com.

Also, voice recognition needs a fast PC and lots of memory. Go for at least a 1.4GHz machine with 128 or 256 megabytes.

Backchat

· Last week, I noted that Windows likes to fill up all the memory available, usually with frequently used Microsoft code. Not everyone likes this idea, and programs such as Freemem claim you get better performance by making more free memory available. David Steele suggests the less well-known RamBooster. However, what really slows Windows 9x (not 200/XP) down is not running out of memory but running out of system resources. There's a good discussion of the difference at www.aumha.org.