I have lost my usb wireless adapter for my Microsoft Wireless Comfort Keyboard 4000, model 1045. How or where do I get another? Or is there another solution?

SOURCE: I lost my installation software for the Microsoft

this will get you the software and driver to run it

http://www.driversquad.com/driver.php?option=b&prodid=473&cust=microsoft%20wireless%20software&channel=search_5891810596_&subid=201_US*DR&roia=!iicYvq1BAAKLOkMAAAYOVQAAZT5CAABnCA-A

SOURCE: My microsoft wireless comfort keyboard

I know your question is a little old, but I just came across it after locating what Microsoft has listed for a manual. It's probably not going to be to helpful since it's more like a quick start guide, but here's what I found.

The only thing that resembles a manual that I could find is here. Looks like more of a quick start guide. On Microsoft's page I could only find reference to the combo on their Korean site.

I was able to find the manual there, which is the same that is listed above. The only other thing that appears to be useful is the data sheet which can be viewed here.

Hope this helps

Ray