"So far everyone has been pretty blah about it," says David Cieslak, a CPA and principal with Arxis Technology of Simi Valley, Calif. Cieslak, a frequent speaker on security issues at CPE events, predicts, "once some high-profile hacks happen folks will begin to pucker."

And on the other side is Wayne Schulz, a CPA who runs Schulz Consulting in Glastonbury, Conn."It is this year's Y2k," says Schulz. "It's a non-event."

So is it a big problem, or is Microsoft simply trying to get customers to shell out for a new operating system? Microsoft has a high-profile warning on its website that spells out what the end of support means: no technical assistance, including automatic updates to fix problems, and lack of compatibility with new applications and devices.

"If you continue to use Windows XP after support ends, your computer will still work but it might become more vulnerable to security risks and viruses," the Microsoft statement says. "Also, as more software and hardware manufacturers continue to optimize for more recent versions of Windows, you can expect to encounter greater numbers of apps and devices that do not work with Windows XP." Microsoft notes that files, settings, and user profiles on systems running XP can be migrated through the use of LapLink's software, but only Windows 7, Windows 8, or Windows 8.1.)

Major users that cannot make the move quickly are reported to be paying Microsoft to maintain the lifeline until they can switch. These include major banks whose ATMs utilizes Windows XP for their service.