Connecting to external MySQL db: "ERROR 1045 (28000): Access denied for user"

I have a website which is hosted on cpanel, and uses and external mysql server.
When the script tries to connect to the external server, following error is generated:

ERROR 1045 (28000): Access denied for user

Same error is shown when I connect to external db from shell, from the server having the website and cpanel.

However, I am able to connect to the external DB from a third server using shell. It means something on the cpanel server stops external mysql connctions.

May I know how to solve this?

PS: This is not "allowing remote connections for mysql database on cpanel server", but opposite of it.

 

That's not the case. I have allowed connections for user@*, and I had already mentioned:

However, I am able to connect to the external DB from a third server using shell. It means something on the cpanel server stops external mysql connctions.

 

I have csf with status: "Firewall Status: Disabled and Stopped"

my.cnf has following values:

Code:

[mysqld]
innodb_file_per_table=1
default-storage-engine=MyISAM
performance-schema=0
max_allowed_packet=268435456
open_files_limit=10000

query_cache_size=64M
query_cache_limit=1M
join_buffer_size=8M
sort_buffer_size = 8M
read_buffer_size = 8M

read_rnd_buffer_size = 4M
max_heap_table_size = 50M
innodb_buffer_pool_size = 1G
table_open_cache = 4000
key_buffer_size = 128M
tmp_table_size = 128M
myisam_sort_buffer_size = 64M