Q My mother-in-law recently gave her old Toshiba laptop to our 14-year-old daughter. It works fine but is a tad slow. It has an Intel Celeron M processor, a chip speed of 1.5 gigahertz, 448 megabytes of RAM and a 55.8-gigabyte hard drive. Is there anything we can do to speed it up without spending a lot of money? Would adding more RAM be worthwhile?

ALDO SANTIN, WINNIPEG, CANADA

A Yes, more RAM would speed up the system. From your description, I think you have a Toshiba Tecra A5-S116 (check your PC to make sure.) Laptops of this type can be upgraded to a total of 2 gigabytes of memory.

Additional RAM modules plug into two memory "slots" on your main circuit board, and are available in increments of 1 gigabyte ($40), 512 megabytes ($24) or 256 megabytes ($14).

For instructions on how to install RAM modules in a laptop, see the YouTube video at tinyurl.com/ya7e5v2.

To find out more about RAM module prices, see tinyurl.com/ye9pqut and tinyurl.com/yabjatm. (You can search for RAM using your laptop's model number.)

Q I recently purchased a new laptop computer with the 64-bit version of the Windows 7 operating system. I'm in the process of purchasing an external hard drive to back up files. Do I need a special hard drive for 64-bit Windows 7, or if I can use any external hard drive?

PATRICK DOYLE, SURPRISE, ARIZ.

A There have been reports of some external hard drives failing to work with the 64-bit version of Windows 7. The problem was that the 64-bit operating system wouldn't accept the drives' "software drivers" -- the software that enables the PC and the hard drive to communicate. Check out Microsoft's list of external drives that are compatible with the 64-bit version of Windows 7 at tinyurl.com/y8screc.

Q I bought the Microsoft Office Small Business 2007 upgrade to replace the 2003 version installed on my desktop PC. But I can't get the upgrade to install. It starts, then quits and displays the message "encountered an error during setup." Microsoft's technicians wouldn't help because I lacked a serial number that's inside the software that won't load. What should I do?

C. KIM STIVERS, LAKEVILLE

A The error you describe seems to be the one on the Microsoft help page at tinyurl.com/ycageop. The page says the upgrade program can't uninstall the 2003 version of Office and suggests you do it manually.

E-mail tech questions to steve.j.alexander @gmail.com, or write to Tech Q&A, 425 Portland Av., Minneapolis, MN 55488-0002. Include name, city and phone number.