A user has recently changed their Kayako Classic database by either upgrading the database version or migrating the server, and is encountering the error below after adding an image or quoting the original email in the ticket reply.
Uncaught Exception AutoExecute Query: AutoExecute Query: UPDATE swticketpostlocks ....
The database change may have turned the default MySQL Strict Mode to the enabled state. When strict mode is enabled, invalid or missing data may cause warnings or errors when attempting to process the query. The preferred state for strict mode when using Kayako Classic should be disabled.
To resolve this problem, strict mode should be disabled following the Disabling MySQL Strict Mode on the Server article.
Once strict mode is disabled, one should be able to reply to tickets without any issues.