On April 8, 2014, Microsoft stopped supporting Windows XP operating system and Microsoft Office 2003 software. Security updates for Microsoft Security Essentials for XP continues until July 14, 2015. Microsoft security updates for web browser Internet Explorer for XP ended some time ago.
Any Windows XP computer system is now vulnerable to malware. Do NOT continue to use your XP computer connected to the Internet. You must make a change immediately. The most expensive option is to buy a new system, move your personal files to it, and give the old machine to the electronic recyclers. The least expensive is to install Linux (Ubuntu version) operating system on your computer. Below are some options to consider.
Replace XP with a Linux Operating System
Linux (linux.com) will run web browsers as well as office software that is compatible with your Windows documents, spreadsheets, etc. Best of all, you can switch for free! First you must choose a "distribution" of Linux (linux.com/directory/Distributions), which may be difficult if you're new to it, so try Ubuntu. Then find additional software. All this can be found here: linux.com/directory.
You may want to study a free course called "Introduction to Linux" (LFS101x.2) at edx.org. You will learn both the graphical interface and command line, covering the major Linux distribution families.
Buy a New Device
Buy a device such as a tablet or a Google Chromebook that can run a variety of apps (software programs). A Chromebook is essentially a web browser without an operating system, but is fine if you already do everything in a web browser with a mouse and keyboard. A free Google account provide you with word processing, spreadsheets, and storage in the "cloud". Tablets are quite different from laptops as they rarely allow you to use a keyboard or a mouse. You can also find inexpensive laptops with Windows 7 or 8 operating systems (Windows 10 will replace both).
Using Windows XP offline only
There's another option - unplug the ethernet or turn off all network connections. You can continue to use XP for non-Internet uses such as specialized XP software, games, word-processing, spreadsheets, and photo editing. But not for email or web browsing.
Using Windows XP on a home network - but not the Internet
This is a varient of the previous option and may be difficult to set up. If you need to connect to other computers and devices in your local network via your home router, then leave the ethernet/Wi-fi network connected but set options so Windows XP is completely blocked from the Internet. (The other devices on the network won't be affected.) To configuring Windows XP to block its access to the Internet:
Using Windows XP connected to the Internet
If you insist on continuing to use your Windows XP system, you need to make these important changes in your software. [Most of the software mentioned is available here: PDQ Library: best free software]
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