SQLite Forum

Get SQLITE_READONLY when using UPDATE command
I think it's time to show your sqlite3_open() call.

It would help rule out a whole category of problems if you were to temporarily substitute for your DB filespec a pathname which you are quite certain can be written by whatever user is getting your unexpected SQLITE_READONLY return. If that continues through the substitution, we can focus on your call. Otherwise, the investigation needs to examine file permissions.