Even the anti-virus guys agree with Danseglio, at least in private. I asked a couple of anti-virus industry people and they said that of course its more desirable to re-image a system. The advantages are huge.
Theres a very high likelihood of success with re-imaging. There are theoretical ways for an attack to slip past a re-imaging, but theyre highly unlikely and most of them, such as EFI-based attacks, can be dealt with through thorough procedure.
There are many good systems available at an enterprise level for managing system images, including tools that come with Windows. If you manage them correctly, recovering a system image can be relatively quick and easy.
Good management practices dictate a system in which all data and user customizations are stored in the profile on the server. Being able to swap in a new image with ease is one of the benefits of following this good practice.
System cleanups can have adverse consequences, breaking applications in some cases. Even where they appear to succeed, the cleaned-up system can not be trusted as it was before infection.
Cleanup can be a long and complicated process, often involving much expert time. Re-imaging, when set up properly, can be a relatively automatic procedure performed without any complicated decision making.
Im sure most enterprises dont actually live in the neat-and-clean world of best-practices that Ive described, but they know its what they should strive for. They also know, or should know, that cleanup is a sub-optimal process.
Next page: Home users have it tough.
Larry Seltzer has been writing software for and English about computers ever since,much to his own amazement,he graduated from the University of Pennsylvania in 1983.
He was one of the authors of NPL and NPL-R, fourth-generation languages for microcomputers by the now-defunct DeskTop Software Corporation. (Larry is sad to find absolutely no hits on any of these +products on Google.) His work at Desktop Software included programming the UCSD p-System, a virtual machine-based operating system with portable binaries that pre-dated Java by more than 10 years.
For several years, he wrote corporate software for Mathematica Policy Research (they're still in business!) and Chase Econometrics (not so lucky) before being forcibly thrown into the consulting market. He bummed around the Philadelphia consulting and contract-programming scenes for a year or two before taking a job at NSTL (National Software Testing Labs) developing product tests and managing contract testing for the computer industry, governments and publication.
In 1991 Larry moved to Massachusetts to become Technical Director of PC Week Labs (now eWeek Labs). He moved within Ziff Davis to New York in 1994 to run testing at Windows Sources. In 1995, he became Technical Director for Internet product testing at PC Magazine and stayed there till 1998.
Since then, he has been writing for numerous other publications, including Fortune Small Business, Windows 2000 Magazine (now Windows and .NET Magazine), ZDNet and Sam Whitmore's Media Survey.