Inputbox cell selection stopped working

[WesJD]

I am calling the InputBox function from a VB.NET application using this line:
StationCell = xlApp.InputBox(Prompt:="Select the first station cell", Default:=rngDefault.AddressLocal, Type:=8)

The inputbox is displayed, and when the user selects a cell, that cell address is supposed to be displayed in the inputbox. This has worked fine for years, but suddenly it has stopped working. The address shown in the box remains $A$1 regardless of where I click in the sheet, and even when I click on the textbox in the inputbox, I can't edit or delete the displayed address. It's like the inputbox refuses to be selected, because if I click on it and start typing, my keystrokes get entered in the last cell I had selected in the spreadsheet. Any ideas?

Thanks!

 

[WesJD]

It turns out that was part of a bigger issue; my keyboard arrow keys also stopped working in Excel, although the rest of the keyboard still worked. Closing and re-opening Excel did not solve the problem, but rebooting did. Weird.