Notes about the BTR file extension:
To open this file type, a required software must be installed. Without it you only see a Windows message "The following file cannot be opened
" (Windows 7) or "How do you want to open this file?
" (Windows 10) if you double-click the file. There click on "More apps"
and choose a suitable software to view such files on your PC or from email attachments.
The BTR file type is primarily associated with 'AviSys' by Jerry Blinn.
AviSys is software for bird watchers (.avi file).
Add-on software also allows the program to catalog butterflies (.btr files), dragonflies (.drg files), and reptiles (.hrp files).
Detailed information for file extension BTR:
File classification: Database
Other applications associated with file type BTR:
'Identifying characters' used on FILExt.com are
provided by Marco Pontello from his TrID database
To change file associations press Windows Key
and then Apps and Features
> Default apps
> Choose default apps by file type
Invalid file associations could be the result of underlying issues within your Windows PC.