As of February 2011, Service Pack 1 (SP1) was the last edition of Windows 7. Microsoft’s “Windows lifecycle fact sheet” indicates that Mainstream Support ended on January 13, 2015; and Extended Support will end on January 14, 2020.
A file with one of these suffixes or file extensions (e.g., “myfile.zip”) has been saved (encoded) in a special compressed format. The “.hqx” and “.zip” and “.sit” formats all are “lossless” — the content and quality of the file’s data are preserved exactly.
Why are these formats used? The first three were invented to correctly transfer data files across the Internet, between different services and computers. They also permit transferring several files in a single “attachment” or archive. Zip’d files, and to a greater degree Stuff’d files, are smaller than uncompressed files. (JPEG or “.jpg” files already are compressed, however.)
The “.pdf” format, established by Adobe, stands for “portable document format.” The PDF format preserves the content and layout of highly formatted documents across all types of computers. For example, a 3-column newsletter will look the same on a PC and Mac. The quality of embedded images and other items may vary, depending on how the PDF document was prepared.
Viewing PDF files requires downloading Adobe’s free Adobe Reader program (or a PDF browser plug-in). Most new computers come with Adobe Reader pre-installed. On Mac OS X systems, the Preview program also can open and read PDF files.
Most modern computers can automatically convert (decode) “.hqx” and “.zip” files so that your word processor, for example, can view the files normally. However, “.sit” (or “.sitx”) files require the free StuffIt Expander or StuffIt Standard program to decompress them.
As of January 2018, my blog contains posts regarding this question, pointing to articles by PC World and test results from independent anti-virus test organizations.
Basically, I recommend using mainstream computer security software like Norton, McAfee, etc.; or, with Windows 10, at least Microsoft’s built-in (free) Windows Defender. And Malwarebytes Anti-Malware (at least the free version).
If you require a “Made in the USA” computer security program, note that there are limited choices.
Note: Cnet January 31, 2018: “Windows will rid your computer of deceitful cleaners.”
Windows Defender will soon delete programs that trick you into paying for a service with alarming messages about the health of your computer.
You’ve likely seen deceitful cleaning or optimizing software in action. After reportedly scanning your computer, this software finds lots of problems, then asks you to pay big to get those problems removed. It tells you your computer is at risk if you don’t cooperate. Thankfully, Windows is going to target and delete those very programs in a March update.
Detecting such “scareware” is a useful update to Defender, something which Malwarebytes Anti-Malware (MWB) has done for years. MWB classifies such rogue software as PUPs (potentially unwanted programs) and also handles PUMs (potentially unwanted modifications).
This PC World article might help answer your question: “Meltdown and Spectre FAQ: How the critical CPU flaws affect PCs and Macs.”
It varies widely depending on your hardware, operating system, and workload.
Massive security vulnerabilities in modern CPUs are forcing a redesign of the kernel software at the heart of all major operating systems. Since the issues—dubbed Meltdown and Spectre—exist in the CPU hardware itself, Windows, Linux, Android, macOS, iOS, Chromebooks, and other operating systems all need to protect against it. And worse, plugging the hole can negatively affect your PC’s performance.
Yeah, I hear you. Here’s a PC World article which might help: “Speed up Windows 10 for free: Tips for a faster PC.”
Is your Windows PC too slow? Give your PC a free performance boost.
It’s a common complaint: My Windows PC is running slow. Annoyingly slow. You can add RAM, or buy a faster SSD, but that costs money. No, your first order of business should be an attempt to wring free performance from Windows. In the following nine steps we show you how to speed up your Windows 10 PC without spending a dime.
Yes, that’s an interesting question since most mobile devices come with gigabytes of so-called free cloud storage for safeguarding your files. The main purpose of such services, however, is to allow you to access your collection of documents, music, photos, etc., from any of your devices and see the same stuff. For example, on an iPhone when you add a photo, it will appear in the Photos app on your Mac. But deleting a photo in either device’s Photos app will remove it from both (because removed from cloud storage — which is reflected on each device).
Syncing may be all that you need in many cases, especially if you are disciplined in tending your collection or you purchase so much storage that you never delete anything. But otherwise you probably want the assurance of a restoration timeline like in Apple’s Time Machine app — you want versions of your collection, whether stuff was deleted later or not.
Reference: PC World, January 31, 2018, “The best free backup software and services: Reviews and buying advice for protecting your data.”
… you say: I have free online storage through Apple’s iCloud or Google Drive, or Microsoft OneDrive. Then there are services like Dropbox, with 5GB for free.
The issue with all those services is that they’re not necessarily true backup, but syncing. That is, when you delete a file from any device or online, it’s deleted from every device. Lord help you if you make a mistake and don’t realize it in time. True backup means retaining data indefinitely no matter what’s happening with the data elsewhere.
Personally, while I have files stored in iCloud, Google Drive, OneDrive, and Dropbox, for local backup of my Mac I use SuperDuper and Time Machine and for my PCs File History and System Image backup.