Vista problem: "Cannot run two device installations" at once

Yet another one of Vista’s endless problems: it keeps telling me that I cannot install my scanner because it “cannot run two device installations at once.” Problem is, I’m not running another installation! How the heck do I get it to stop bugging me about this? I can only find information on fixing the problem in XP, and I’m finding that the XP solution doesn’t apply in Vista. Any help?

someone here solved the problem by turning off his firewall temporarily. You might try that.