Issues connecting to FTP over Implicit TLS/SSL

[Sherlock25]

I am having trouble connecting to an FTP Server using Implicit TLS/SSL on Port 990. From the same computer, I am able to connect with FileZilla with no problems at all.

BestSync Settings Used:
Client: BestSync 10.0.3.6 Business License
Protocol: FTP / Implicit TLS/SSL / Port 990 / Passive Mode
Log:
Error: Failed to connect to ftp.ftpserver.com Error:(null)
winsock:Receive::Error.:error:(0x00002746):An existing connection was forcibly closed by the remote host.
>USER ftp_user
>TYPE A
>PBSZ 0
>PROT P
>PASV
>PASV
>PASV
>PASV
>PASV

FileZilla Settings Used:
Client: FileZilla 3.12.0.2
Protocol: FTP / Implicit TLS/SSL / Port 990 / Passive Mode
Log:
Status: Resolving address of ftp.ftpserver.com
Status: Connecting to ftp.ftpserver.com:990...
Status: Connection established, initializing TLS...
Status: Verifying certificate...
Status: TLS connection established, waiting for welcome message...
Status: Connected
Status: Retrieving directory listing...
Status: Directory listing of "/" successful

[RiseFly]

Please check if the firewall settings have be set correctly.
Here is the Q&A page about the FTP setting:
http://www.risefly.com/fseqna_ftp.htm

[Sherlock25]

The Windows Firewall on this PC is disabled. There is no 3rd party Firewall or anti-virus installed on this PC.

[Sherlock25]

Just wanted to follow up if see if you have any other ideas.

I have also tried connecting with AlexFTPS client as well as File Zilla. I am able to connect with both clients without an issue. I am only having issue connecting with BestSync.

I get the following error with BestSync:
winsock:Receive::Error.:error:(0x00002746):An existing connection was forcibly closed by the remote host.