I cannot find the Preference Tab in the Smart Zone Communications Center. Trying to set my signature and having all kinds of issues.
Comcast hasn't use that name for their webmail for at least 5 years. Shortly after they began using the Xfinity brand name, "SmartZone Communications Center" was renamed to "Xfinity Connect".
If you have Comcast's latest Open-Xchange "Appsuite" webmail ("...connect.xfinity.com/appsuite/..."), there is no Preference tab. To manage signatures, see the Signature items on the https://www.xfinity.com/support/articles/xfinity-connect-advanced-features-new-experience page. Also see https://connect.xfinity.com/appsuite/apps/faq/index.html.