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You must define which URL you want your users to receive, say suppose the domain that is going to be used is the "penskefascredit.com", so your document collection URL is going to be sub-domain of that. Could it be “documents.penskefascredit.com”. The first word of the domain indicates the sub-domain of 'penskefascredit.com'
Buy an SSL certificate for this domain and generate the .pfx file of the purchased certificate (using the SSL cert, bundle, and private key that was used to purchase SSL.)
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Go to the website where your 'penskefascredit.com ' domain was purchased and update the DNS records. You are going to need to add a new CNAME record.
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If the sub-domain chosen in step 1 was “documents.penskefascredit.com" then the following CNAME must be created:
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