App-V Sequencer 5.x cannot sequence apps with filenames "CO_x" (Error 0x8007139F). But it is possible !!

Recently I came across the App-V technical document stating that

"The App-V 5.x Sequencer cannot sequence applications with filenames matching "CO_<x>" where x is any numeral. Error 0x8007139F will be generated."

https://docs.microsoft.com/en-us/microsoft-desktop-optimization-pack/appv-v5/creating-and-managing-app-v-51-virtualized-applications



https://github.com/Microsoft/windows-itpro-docs/blob/master/windows/application-management/app-v/appv-release-notes-for-appv-for-windows.md















So I ran a quick test to confirm on the same.I used App-V 5.1 sequencer and App-V 5.1.86 client for testing.

During monitoring phase, I created a New folder in desktop for convenience.I then created 3 new files with different extensions (CO_123, CO_456.txt, CO_897.dll) and then proceeded stopping the monitoring phase. I was expecting that sequencer will throw an error or fail as mentioned in the Microsoft technical document. To my surprise sequencer completed without any issues. I was able to see the files in Package Files tab in the sequencer package editor.











To confirm, I also published the test package in a standalone machine and saw those files getting reflected.

UPDATE 6/22/2017: One of my friend Roy Essers had a query asking whether this happens when sequenced to PVAD. Since I didn't test this scenario in PVAD, I quickly ran a test by enabling the sequencer with -EnablePVADControl and gave c:\program files\CO as PVAD folder.



















In that folder I then created the below files.













After creating I stopped the monitoring and sequencer didn't show any error even this time. It successfully created the package. Even in client testing it got succeeded.


So to finalize, App-V 5.1 Sequencer can sequence apps with filenames having "CO_<x>" without any issues. This is just a experimental test scenario and if anyone have faced the issue having CO_<x> in their package while sequencing, kindly comment below about the application. I will be happy to validate it further and update this blog post.