AST-Link cannot connect

Uploading files for Closed Captioning using CaptionSync's AST-Link can be affected by the quality of your connection. This article shows some troubleshooting tips.

After you've succeeded in setting up AST-Link with your public key, it worked for a while but now it suddenly stops working (including the Fatal: Server Unexpectedly Closed Network Connection message in the Windows AST-Link), it's possible you've been inadvertently blacklisted by our server.

Did you make any changes to your AST-Link settings?

• If not read on.
• If you did, jump down to Other AST-Link Issues below.

Blacklist Background

Blacklisting can happen for one of two reasons:

1. There was an SFTP login attempt via password instead via public key
2. There was an SFTP connection without any IDENT info sent.

Rule #1 could only happen if you are manually connecting via SFTP and are passing a password instead of the public key (AST-Link itself will not try to send a password). But rule #2 may inadvertently happen if there is network error just when you are trying to connect our server.

Once a particular IP address (machine) meets one of these two conditions, it is blacklisted. If this is the case, you need to open a support ticket to have the IP address removed from the blacklist.

Whitelist Background

When you log into the CaptionSync website successfully, your IP address (machine) is added to the whitelist of trusted users.

Take Away

The system checks the IP address (machine) against the whitelist of trusted users before adding to the blacklist for rule #2. So be sure to log into the CaptionSync website successfully from the same IP address (machine) where you are running AST-Link to avoid potentially be blacklisted due to a network error. You need to remember to do this early, because once you're blacklisted, AST-Link won't work anymore...

If your support says you have not been blacklisted, read on...

Other AST-Link Issues

Permissions Error (Mac)

 If when you drag a file to AST-Link for Mac, and see a message like this:

This means AST-Link tried to connect, but it failed to authenticate.  Make sure your SSH key has not been deleted or overwritten on your Mac!  Also check that it has not been accidentally disabled on SSH Keys page under the Settings tab...

Unable to Read Preferences (Windows)

If when you start up AST-Link for Windows you get an error message like Pref files cannot be read from server., and/or  C:\...\AutomaticSync\ast_YourUserID.prefs: Cannot Create File., then this could mean some changes were made to the registry settings (for example, changing your Windows username), and you'll need to reinstall the app. Just follow the installation steps outlined in our tutorial. Note that you can reuse the SSH key you had been using so far, so you can skip the steps under "Setting up AST-Link", between 1 and 9. On step 10, enter your CaptionSync user ID and provide the path to the private key you had been using so far. Then check if AST-Link can connect to us. If this is successful you'll see the Server Ready message in green, at the top.

Stuck Reading Preferences (Windows)

If when you start up AST-Link for Windows it tries to connect, but it gets stuck reading the preferences (i.e. you see this):

What may be happening is that your IT department has restricted access to destination port 22 via your corporate firewall. Port 22 the standard SFTP port and is needed for AST-Link to connect to the CaptionSync server. See testing port 22 below...

Appears Not Ready (Windows)

If your AST-Link for Windows screen looks like this (with the Server Ready in green at the top, but Not Ready in orange beside your media file), you have successfully connected:

What that means is that AST-Link did not find a text transcript for the media file (needs to be the same base name). If you don't have a transcript (i.e. you want us to transcribe it), then what you need to do is check the Transcript Requested checkbox in the upper right before you submit.

Testing Destination Port 22 (Windows)

To test whether destination port 22 is restricted via your corporate firewall or not, you can try to connect to any arbitrary external SFTP server. Here's a relatively easy way laid out below.

• Install Filezilla client SFTP program (it's free).
• Once installed, set the host to sdf.org, set the username to anything (test for example), the password to anything (xxxx is fine), and the port to 22.
• Click the Quickconnect button.

If you see the following in the top status pane, port 22 is open (you just didn't have a valid username/password):

Alternatively if you see the following in the top status pane, port 22 is NOT open:

If Destination Port 22 is Open

If port 22 is open, the next thing to check is if clearing out the registry will help.

1. Quit AST-Link.
2. Under the Start Menu choose Run, then enter Regedit.
3. In Regedit use Edit → Find to locate AutomaticSync. Check Match whole string only and click Find Next.

   

   

4. Once you see AutomaticSync on the left-hand column, under Software, delete this entire entry:
   

   

5. Quit Regedit.
6. Start AST-Link and it will ask you for your AST username (lowercase) and the location of the private key pertaining to the public key on the CaptionSync website.

If this fails to resolve the issue, please open a support ticket and we'll dig into it further...

If Destination Port 22 NOT Open

If port 22 is not open, there are a few options:

• Petition your IT department to allow you to connect to destination port 22
• Run AST-Link on a laptop from home or Starbucks, thereby circumventing the corporate firewall
• If you have access to a Mac, run the Mac version of AST-Link which falls back to using port destination 443 if port 22 is not open.

Testing Destination Port 22 and/or Port 443 (Mac)

To test whether destination port 22 is restricted via your corporate firewall or not, you can try to connect to any arbitrary external SFTP server. Here's a relatively easy way laid out below.

• Open Terminal.app (it's in the Utilities folder under Applications).
• At the command prompt (after the $) type the following:

$ sftp -P 22 test@sdf.org

If Destination Port 22 is Open

You will see something like the following

The authenticity of host 'sdf.org (192.94.73.15)' can't be established.
RSA key fingerprint is 53:2a:b3:92:a6:88:ca:c0:ff:c2:1b:d1:53:11:fc:4e.
Are you sure you want to continue connecting (yes/no)?

At this point you can type no and quit Terminal.app.

If Destination Port 22 is NOT Open

You will see something like the following

ssh: connect to host sdf.org port 22: Operation timed out
Connection closed

You can similarly test if port 443 is blocked by changing the -P 22 to -P 443 and run the above command again.

If port 443 is open, you can re-run the AST-Link for Mac install and it will fall back to use port 443.  If both port 22 and 443 are not open, there are a few options:

• Petition your IT department to allow you to connect to destination port 22 or 443
• Run AST-Link on a laptop from home or Starbucks, thereby circumventing the corporate firewall