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Disinfectant Update

Apple’s Compatibility Checker erroneously claimed that John Norstad’s incredibly popular virus checking utility, Disinfectant, was up to version 2.5. However, Norstad, ever the nice guy, decided to give Disinfectant a small update to make Apple feel better, so now we have a real Disinfectant 2.5. Little has changed, other than the ability to find the new ZUC C virus from Italy and the MDEF D virus, which probably never made it into public circulation. Neither is nasty or widespread, so don’t get all worried again. Disinfectant will no longer support old 64K ROMs (the Mac 128K and 512K) and all versions of the system before 6.0, which is a bit more common, especially among the double-floppy crowd. Apple’s MPW no longer supports those Macs or systems, so Norstad had no choice in the matter, short of switching development systems. The final two changes include a bug fix for an error that sometimes caused Disinfectant to crash after printing the manual, especially to DeskWriters, and an added manual section dealing with System 7.

Speaking of System 7, there are three rules to keep in mind when dealing with Disinfectant (and I believe these apply to 2.4 as well). (1) Leave the Disinfectant INIT in the System Folder proper. Don’t move it to the Extensions folder. If you are mucking around with moving extensions around, System 7 will try to make you put it in the Extensions folder, but I suspect you could just install a new version from the program to get around that. I personally just got irritated at System 7 and used DiskTop to change the type to something other than INIT, moved it into the System Folder, and then changed the type back to INIT. (2) Disinfectant sometimes prefers to work on a file while not in MultiFinder. Since you can’t shut MultiFinder off in System 7, try rebooting with an old System 6 boot disk (the Disk Tools disk in System 7 is actually a System 6 boot disk) and running Disinfectant again. (3) Don’t try to select anything in the DeskTop folder to be scanned via the get file dialog since Disinfectant may crash or scan the wrong file.

I’m surprised John decided to release 2.5 because I had been under the impression that he was working on 3.0 for the next public release. Disinfectant 3.0 should be pretty cool, what with Balloon help, color icons, icon dropping in the Finder (you can tell when your Mac’s infested when you start finding icon droppings :-)), anti-viral and other events, and correct placement of the Disinfectant Extension (which will no longer have to load last) and the Disinfectant Preferences file. Another feature that everyone will appreciate is an Upgrade command that will allow users to download very small upgrade files and use them to upgrade the entire program, thus saving significantly on download time. As usual, Disinfectant’s fine online manual will be upgraded to include a thorough discussion of viruses in System 7 (the Desktop viruses like WDEF and CDEF will just stop working, for instance).

The only thing Disinfectant won’t do when it comes out later this summer (other than cure the common computer cold) is block infected applications from gaining access to a system via file sharing. Since network volumes are just like any other volume, there is no way, now or in the future, of preventing that. However, Disinfectant will block any virus spreading attempts, so the security breach is not all that major unless you fail to check your hard disk with Disinfectant every now and then.

Information from:
John Norstad — [email protected]

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