Unable to send file to MOVEit Transfer using MOVEit Automation.
Automation tasks that attempt to upload files to Transfer server after upgrading to the Jan 2024 service pack fail with Could not upload file into MOVEit DMZ folder <number> on server <server name>: HttpSendRequestEx failed: The attempt to connect to the server failed.

dmz_isapi.log contained the following error:

2024-03-21 09:19:00.529  92c:DoEntirePost: StartPost ret The attempt to connect to the server failed.
2024-03-21 09:19:00.529  92c:m2 transaction to machine2 ret 12029
2024-03-21 09:19:00.529  92c:TellsiLockToStartUpload: m_szInstitution=
2024-03-21 09:19:00.529  92c:SetCheckpointFilePath: Input file ID is empty string
2024-03-21 09:19:00.529  92c:DeleteCheckpointFile: Checkpoint file path is empty string
2024-03-21 09:19:00.529  92c:Can't tell Transfer to start upload: HttpSendRequestEx failed: The attempt to connect to the server failed.
2024-03-21 09:19:00.529  92c:AppendUTF8HeaderToClient: szHeaderName=X-siLock-ErrorCode szHeaderValue=3201
2024-03-21 09:19:00.529  92c:UTF8ToHeaderIfAccepted: m_bClientAcceptsQEncoding=true val=3201
2024-03-21 09:19:00.529  92c:AppendUTF8HeaderToClient: szHeaderName=X-siLock-ErrorDescription szHeaderValue=HttpSendRequestEx failed: The attempt to connect to the server failed.
2024-03-21 09:19:00.529  92c:UTF8ToHeaderIfAccepted: m_bClientAcceptsQEncoding=true val=HttpSendRequestEx failed: The attempt to connect to the server failed.
2024-03-21 09:19:00.529  92c:MOVEitISAPI sending headers to client:
Cache-Control: no-cache, no-store
Pragma: no-cache
Expires: -1
Content-Type: text/plain
X-siLock-CanAcceptNonLumpHash: 1
X-siLock-ErrorCode: 3201
X-siLock-ErrorDescription: HttpSendRequestEx failed: The attempt to connect to the server failed.
 

Tasks that use sftp have no issue uploading or downloading files.
Connecting from the Automation PC to the Transfer server using the Web UI can successfully upload/download and delete files.

There could be several causes to this error, including but not limited to: 

• This error will often happen because the site binding for on the Transfer website was removed or incorrectly configured.
• It may also happen when Automation tasks are connecting to MOVEit Cloud and the IP address is locked out.
• It is possible that having PKCS key exchange (SSL/TLS) DISABLED in the registry could be causing the tasks to fail.

Option 1:

In Transfer config, in the paths tab, Machine contained the following:
https://<mamachine.mycompany.com>/machine.aspx
Machine2 contained the following:
https://<mamachine.mycompany.com>/machine2.aspx

Change Machine to http://localhost/machine.aspx
Machine 2 should change to http://localhost/machine2.aspx

Transfer Config Utility:
https://docs.ipswitch.com/MOVEit/Transfer2021/Help/Admin/en/index.htm#23464.htm

This may resolve the issue in some instances and not others.
diabling URL redirect (IIS) may resolve the issue but some sites may see this as a potential security risk.

Enable PKCS key exchange. One method for doing this is using IISCrypto (https://www.nartac.com/Products/IISCrypto).
In one case, enabling PKCS key exchange allowed Automation to successfully connect to Transfer over HTTPs. 
Note: this involves a change to the Windows registry. A backup of the registry should be made prior to making changes to the registry.



The registry entry is as follows:
Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\KeyExchangeAlgorithms\PKCS

Option 2: 

To check whether the site bindings are causing the issue:

1. Press the windows key
2. Type 'run'
3. Type 'inetmgr'
4. Expand the local computer
5. Expand sites
6. Select moveitdmz
7. In the Action panel click 'Bindings...'

It should show that both ports 80 and 443 are bound. If not, they should be added in order to resolve these HTTP errors.

To add this binding (please discuss this with your network/security team to confirm this is the proper setting for your environment):

1. Click 'Add..."
2. Type 'http'
3. IP Address 'All Unassigned'
4. Port '80'
5. Host Name ' '

In another case under IIS for the MOVEit Transfer web page Directory Browsing was found to be enabled (on). Disabling this is IIS solved the issue.
If connecting to MOVEit Cloud, check for IP lockouts. Remove them if present, and wait a few minutes to give it time to process.

Try using sftp in place of https.

Debugging tip:
On the Transer server look for C:\Program Files\MOVEit\Clients\MOVEit-Transfer-ClientTools.zip
In that zip file is a client entitled Xfer.
Run as follows:
Xfer -z https://localhost
The executable promots for a username and password.
Enter a known valid username and password.
A valid username and password should provide an Xfer prompt. 
Enter quit to exit.

Next run Xfer again and follow the instructions above except enter an invalid username and password.
An error message should result: 'Invalid username/password or not allowed to sign on from this location'.

Any other response indicates an error that might refer to the PKCS issue described above.