'Invalid utf8 character string' warning when importing into AWS RDS MySQL I am trying to migrate osTicket from physical Windows machine to AWS RDS, and I get a bunch of warnings while doing so. I am quite a DB noob, so I am not sure what is the issue.

Source: Windows, MySQL 5.6.10, backup created with mysqldump -u root -p --default-character-set=utf8 osTicket > file.sql

mysql&gt; show variables like 'character_set%';
+--------------------------+---------------------------------------------------+
| Variable_name            | Value                                             |
+--------------------------+----------------------------------------------------
| character_set_client     | cp850                                             |                                            
| character_set_connection | cp850                                             |
| character_set_database   | utf8                                              |
| character_set_filesystem | binary                                            |
| character_set_results    | cp850                                             |  
| character_set_server     | utf8                                              |
| character_set_system     | utf8                                              |
| character_sets_dir       | C:\Program Files\MySQL\MySQL Server 5.6\share\char|
|sets\                                                                         |


Destination: AWS RDS, MySQL 5.6.27-log, import with mysql> source file.sql. I've created a custom Parameter Group to change character_set_database to utf8 since default on RDS is latin1

mysql&gt; show variables like 'character_set%';
+--------------------------+---------------------------------------------------+
| Variable_name            | Value                                             |
+--------------------------+----------------------------------------------------
| character_set_client     | cp850                                             |                                            
| character_set_connection | cp850                                             |
| character_set_database   | utf8                                              |
| character_set_filesystem | binary                                            |
| character_set_results    | cp850                                             |  
| character_set_server     | utf8                                              |
| character_set_system     | utf8                                              |
| character_sets_dir       | /rdsdbbin/mysql-5.6.27.R1/share/charsets/         |


I get warnings like these: 

Warning (Code 1300): Invalid utf8 character string: 'FFD8FF'
Warning (Code 1300): Invalid utf8 character string: 'FFD8FF'
Query OK, 6 rows affected, 6 warnings (0.06 sec)
Records: 6  Duplicates: 0  Warnings: 6

Warning (Code 1300): Invalid utf8 character string: 'FFD8FF'
Warning (Code 1300): Invalid utf8 character string: 'FFD8FF'
Warning (Code 1300): Invalid utf8 character string: 'FFD8FF'
Warning (Code 1300): Invalid utf8 character string: 'E2E3CF'
Warning (Code 1300): Invalid utf8 character string: 'D0CF11'
Warning (Code 1300): Invalid utf8 character string: 'E2E3CF'
Query OK, 20 rows affected, 20 warnings (0.06 sec)
Records: 20  Duplicates: 0  Warnings: 20


I tried to set character_set_client=cp850 and the same for set_connection and set_results before import, but didn't help me.

If anyone could be so kind to help me what I am doing wrong here, it would be really great.

Thanks in advance!
Judging by your initial post, where you said you used default options for mysqldump, it means you didn't use the --hex-blob option. I've played around with osTicket some time ago, and you should definitely used --hex-blob option to create your dump. It will give you much bigger .sql file (and of course, the import to RDS will take more time) but in that way you won't get the UTF8 warnings you're getting now, and your attachments will be available once you deploy osTicket to new host.

One more advice, update to newer versions (1.9 or 1.10) and move those files out of DB, you can use S3 or even EFS now, or just store it under your EBS volume