>My clients Hardware people loaded a service pack to their Windows 95 machines to make them "y2k" compliant. Since then they have been getting error 1958 sporadically when printing. Anybody have experience with this issue, or know why a service pack would start this behavior? TIA.
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I've seen it; one way to cause it to happen consitently is for the driver for the referenced printer to reside on another system, and that system to not be available at the moment. It's not the only time I've seen it. What's worse, it may not be the system that got the SP applied to it that sees the error; it might be something that got fried in File and Printer Sharing on the machine that owns the copy of the driver. IOW, either the host (server) or the client PC might be at fault here.

Windows may reference the current driver installed on another system with a printer that was shared through the MS Networking Client; if several similar printers are defined on the network, your own system relies on a networked copy of the driver and the system that has the printer driver is cooked (it might not be the system sharing the printer you've switched to, just the first place that the affected system found that referenced that driver), this error appears consistently. It seems to happen a lot less if each machine has the drivers defined locally rather than inherited from the machine sharing the printers. It also seems to happen a whole lot more with peer-to-peer environments.

Reinstalling the printer drivers locally seems to help.