This is a pesky one. The last step of the decommissioning of an Exchange 2003 server from the Add/Remove Programs option (after correctly removing all per-requisites) and bam- this error pops up on uninstall.
Reason being- the error points to (but does not explain) the installation media path/disk not being able to be found so the uninstall can continue. Now, I’d seen this before with another uninstall but it actually prompted me for a network path for the media (This was Exchange 2003 Std versus Enterprise this time, but really this shouldn’t differ!)
- Run the setup from the Exchange media and uninstall this way or
- Download the media (if you’d lost it like I had) and uninstall as per above.
That worked a treat.