We are running MOSS 2007 Ent. Edition, and recently upgraded all client PCs to Vista Enterprise with Office 2007 installed. All patches up to current.
In any case, Office Products all had issues saving directly to SharePoint, Explorer View fails, and "Open in Windows Explorer" prompts repeatedly for credentials and ultimately fails.
The workaround is simple to implement.
Open 'My Computer'
Right-click and select 'Add a network location'
Click Next Next Next then in the textbox requiring the location to add enter the root of your portal.
Example https://portalname
Click Next Next Next then Finish
You are done. This resolves MANY Office issue and allows IE to open lists in Explorer View.
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