Some movies play on windows Kodi but don't play on FireTV. No add ons. Both latest stable release something .9 . 18.9? Playing AVI files.
To receive meaningful assistance you will need to provide a full debug log.
The instructions are here...
debug log (wiki)
If you are using the Basic Method, then ensure the following is applied...
1.
Enable debugging in Settings>System Settings>Logging,
2.
Restart Kodi
3.
Replicate the problem.
4.
Upload the log to
Kodi Paste Site manually or use the
Kodi Logfile Uploader. (wiki) With either method post the link to the log back here.
If you are using the Advanced Method ensure you have correctly created and applied the
advancedsettings.xml file (wiki)
In both instances, you should see the word
DEBUG throughout the log.
Note: Full logs only. No partial or redacted logs
Do NOT post your logs directly into the forum. Use the Kodi Paste Site. Post the link to your pasted log in the forum
Uhm, how do I extract debug logs on FireTV?
https://kodi.wiki/view/Add-on:Kodi_Logfile_Uploader