Q: A local repair shop fixed my PC after it was attacked by a virus, but a few days later I noticed that I couldn't open some of my documents and photos. The repair people don't know what happened, so I'm sending you some of my files. Can they be recovered?
Evelyn Trinidad, Miami Beach, FLA.
A: Although your photos are labeled as being in the JPEG format used by most digital cameras, my photo software says they are "not valid" JPEG files. Your Microsoft Word file can be opened, but contains only gibberish.
I believe that malicious software has encrypted, or coded, your files to make them unreadable. Programs that do this are called "ransomware" because they usually display a message that's the equivalent of a ransom note: If you want your files unencrypted, you have to pay the hackers responsible using a prepaid credit card (so that the transaction can't be canceled later.) If you pay, the hackers may or may not use an encryption key, which only they have, to unlock your files and return them to normal.
Since you haven't received the ultimatum, I think your computer repair people probably removed both the ransomware program and the ransom note when they cleaned your computer. This had the secondary effect of severing your only means of communicating with the hackers. As a result, your files will remain encrypted and are gone for good.
This is both bad and good. You can't get your files back, but you also weren't tempted to pay these creeps to restore your files.
How can you avoid having this happen again? The best-known ransomware program is called CryptoLocker (see tinyurl.com/pno3z7w), and it's usually spread through "phishing e-mails" that appear to be from legitimate companies. Phishing e-mails try to trick you into clicking on a link to a website that contains malicious software. Don't click on these links, no matter how authentic the e-mail appears to be. In addition, make backups of your important data on an external hard drive, flash drive or online storage site.
Q: In the last six months I've had problems with my work computer slowing down, sometimes for as much as 20 seconds. A little box on the screen shows what's stalled (such as downloading an e-mail attachment) and asks if I want to "Wait" or "Cancel." If I wait, the PC resumes working.
My colleagues have cleaned up the computer, but it hasn't done any good. I wonder if the slowdowns are caused by the capacity of my PC, my Internet service provider or my Google Chrome browser. Any ideas?
Tomm Johnson, Edina
A: The consensus in online forums (see tinyurl.com/o5ps9e9) is that the problem is caused by an unintentional software error (what programmers call a "bug") in the Google Chrome browser. I suggest you download a newer version of Chrome, in which the problem has likely been fixed, or switch to another browser, such as Mozilla Firefox (see tinyurl.com/pjk39hl.)
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