HTTP 400 · Bad Request
HTTP 400 Other

When & why it happens

The client has to be updated in order to support file references. Treated by gogram as a regular API error; inspect ErrResponseCode.Message for the exact code.

Handling in gogram

Surfaced as *gogram.ErrResponseCode. Match on the message:

if err, ok := err.(*gogram.ErrResponseCode); ok { if err.Message == "FILEREF_UPGRADE_NEEDED" { // handle this error } }