Q: I have a Toshiba laptop and am using Mozilla Firefox as my Web browser. About every third day I get this message: "Plug in container for Firefox has stopped working." What does this mean and what do I need to do to fix it?

— Jacquelyn DeLeon

A: Software development is tricky enough when it's just one program, but when you have two programs — and two development teams — trying to make programs work together, it's even more challenging. And when updates happen frequently, as can be the case with browsers, it's all too easy for incompatibilities to raise their heads.

It would appear that such an incompatibility has emerged between Firefox and one of your plugins. To find the culprit, call up Firefox's Add-ons Manager and select the Plugins button. Next, disable all your plugins. Finally, enable your plugins one by one until the problem recurs.

Once you locate the misbehaving plugin, you may want to disable it until the vendor provides an updated version.

Q: I have a desktop with a solid-state (SSD) drive that has more than 90 gigabytes of stuff on it. I've tried to be careful about putting my data on another drive. My question is how can I go about freeing up space on the SSD? I don't want to get rid of software that I need. Is there a utility out there that can help with this?

— Jay Henderson

A: Windows has a built-in utility that helps you rid your hard drives of clutter. Call up Windows Explorer and right-click on the drive you want to clean up. Select the Properties option. In the dialog box that opens, click on the General tab and then on the Disk Cleanup button.

The utility will take a few moments to scan your drive, then will offer you a list of various types of files you can selectively remove. It also lists how much space is occupied by each type of file.

I just checked one of my drives, for example, and found, among other things, 12 megabytes of archived Windows error reports, 2 megabytes of offline Web pages and 1.4 megabytes of temporary Internet files.

In all, the system found 45 megabytes of space to reclaim. When I had the utility include system files, it found 10 more megabytes.

Q: I have a Dell Inspiron 9400 in which Windows Vista was originally installed. I converted to Windows 7 about a year ago. It seemed fine until most recently. Now it locks up — freezes — and you can't do a thing except turn it off with the off button. I can't even get to anything on the screen.

We do get a message that "Windows Explorer has quit operating." The screen gets a white glaze and the message gives a choice to "restart Explorer" or "stop Explorer" or something similar. But no matter what we do, there is never anything we can get to work. So we turn it off.

I have thought of reinstalling Windows 7 from the discs I have, but I'm not sure that is the right thing to do and I don't want to screw things up.

I do have Windows 7 discs from a new Latitude PC (64-bit) but don't know if they would work on the Inspiron, which is 32-bit.

Any ideas?.

— Greer Allen, Kirkland

A: First, check whether you have a virus or other malware running on the computer. Some viruses can survive a reinstall, so it's important to find out. I'd do a full scan with your anti-virus software and then run Malwarebyte's Antimalware, a no-cost download at www.malwarebytes.org.

Next, I'd try uninstalling and then reinstalling Internet Explorer, or perhaps another browser.

If nothing evil turns up in those scans and if reinstalling the browser doesn't solve the problem, I'd then reinstall from the Windows 7 disc, reformatting the hard drive during the installation procedure.

No, don't try to install the 64-bit version. It won't work on a 32-bit computer. And don't forget to back up any data.

Questions for Patrick Marshall may be sent by e-mail to pmarshall@seattletimes.com or pgmarshall@pgmarshall.net, or by mail at Q&A/Technology, The Seattle Times, P.O. Box 70, Seattle, WA 98111. More columns at www.seattletimes.com/

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