Quick Q: SIP URL in Microsoft Access & misc?

Thanks for all your help . So I use voice over ip for my work phone
calls and I have all my client files in Excel so I am able to use the
Sip Url code to make calls directly from my Excel but on Access it
doesn't seem to let me. I like access and its Contact Organizer because
it has a lot more functionality.

One side note: what are digital signatures exactly? My work emails
often times end up in client's spam folders (maybe because it has "loan"
in the email address). If I acquired a digital signature, would it stop
this or is there anything I can do???

Thanks so much and I appreciate all the help!


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xxsassxx31