Unable to delete old calendars from Microsoft Outlook Android App Software: 


Microsoft Outlook App on Android
Microsoft Outlook for Windows, version 2007


I currently have a work account which I have synced with my Android, and for some reason, all of the calendars I've ever accepted on my work's account (and deleted on my desktop) are still showing up on my Outlook App on my Android.

Aside from being annoying (given that all their respective reminders are still popping up), I have on many occasions accidentally added a new reminder onto an old calendar which, if isn't a "shown" calendar, ends up hidden and I never know about it.
I found this discussion helpful: 

http://answers.microsoft.com/en-us/outlook_com/forum/osettings-ocalset/deleted-calendar-showing-up-in-ios-outlook-app/2812d42a-4bdd-464c-9077-b1517d6f665c

What worked in my case was: 

1.deleting both outlook account from account settings AND outlook app


creating microsoft exchange account according to instructions from the link above
installing once again outlook app, but this time using not outlook settings but Microsoft Exchange settings