Jump to URL/File path to local file shouldn't have double slashes

I'm linking to pdfs from buttons on the stage. I set up the Trigger Wizard and it works. But when I return to this dialog, I find that the path to the local file now has double slashes instead of single slashes. Clicking the green check button yields a Windows Explorer message saying this file does not exist.

I'm not sure what's happening, but I've had to reset the path by taking out the extra slashes.