Applies to
All UCX Suite versions.
Description
Connection to a POP3/IMAP/SMTP server using a secured channel (SSL or TLS) can take a long time (even 75 seconds) on UCX Suite servers that are in a workgroup and isolated from Internet.
You can experience this also on the UCX WEB page pressing the "Test" button.
Cause
When a secure connection is established with an external mail server (including GMail and Office365), Windows tires to verify if the remote server certificate is a trusted (and not revocated) certificate.
Normally this is done querying the local CA (domain controller); if the UCX server is not in a Windows Domain, this check is attempted online invoking an HTTPS Windows Update URL .
If the machine is isolated form Internet this attempt can fail with a very long timeout (up to 75 seconds).
Solution
Edit the local policies of the server reducing the connection timeout for the Certificate Path Validation.
Below the required steps.
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Execute gpedit.msc with admin privileges.
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Select Windows Settings -> Security Settings -> Public Key Policies -> Certificate Path Validation Settings.
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Edit the properties of Certificate Path Validation Settings, select the Network Retrieval tab.
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Enable the flag "Define these policy settings", disable the other ones and set the two retrieval timeout to 1 second.
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Apply the change, then restart Digital Fax and IIS services.