This is a blog following the one I already wrote ealier:  https://www.dbi-services.com/blog/documentum-administrator-ucf-troubleshooting/
The first one was for “how to find the error” and not how to resolve it. In this blog I will talk about an error I got by a customer about UCF.

I got an error message using DA 7.2 where I coulnd’t download documents, in fact every transfer were failing due to UCF. By following my previous blog I found the specific error in the logs saying:
SSL Handshake failed.

You probably had this issue as well if you used SSL with DA. By default when you configure SSL with DA it tries to find a certificate from the java CA cert. You can add the certificate to your keystore to prevent this issue.
But in my case I had a keystore generated from certs certified by the customer authority. So I had to find another way.

I found the solution in the documentation: https://support.emc.com/docu56531_Documentum-Web-Development-Kit-6.8-Development-Guide.pdf?language=en_US at page 58.

You can deactivate the java validation as follow:
cd $CATALINA_HOME_DA
vi ./webapps/da/wdk/contentXfer/ucf.installer.config.xml

Add the following option:

<option name="https.host.validation" persistent="false">
<value>false</value>
</option>

Now restart tomcat or your application server and you will be able to transfer content.