I frequently get an error message in Visio 2013 when exporting a PDF file of “This file is open in another instance of Visio or in another program”
I am not sure exactly what causes the error. Others have reported this issue being caused by their antivirus software, but I have tried disabling by AV when this occurs and it has made no different. Here are a couple things that have worked for me to get around it:
Uncheck the “Automatically view file after saving” option in the save dialogue box.
Go into the Windows Task Manager and end the “Adobe Reader and Acrobat Manager” task. Microsoft and Adobe do not seem to like to play well with each other and sometimes closing the Adobe task fixes the Visio error.
Instead of trying to save to a PDF go into Print instead and Print to a PDF using the Adobe PDF printer or a program like CutePDF.
A more extreme fix is to exit Visio and go back in again, but this is quite annoying since exporting a PDF should be a pretty basic task.