231 Pa. Code Rule 3028
(b) If service cannot be made as provided by subdivision (a), then service may be made
(1) in the manner prescribed by order of court pursuant to Rule 430(a), or
Official Note
For example, where the Postal Service shows a good address and mail service under subdivision (a) is returned unclaimed, the court pursuant to Rule 430 may permit service by regular mail.
(2) by publication in the manner prescribed by Rule 430(b) upon the filing of an affidavit showing reasonable efforts to make service pursuant to subdivision (a) and the reasons why such service could not be made.
Official Note
A special order of court under Rule 430(a) is not a prerequisite to service by publication under this rule.
The provisions of this Rule 3028 adopted October 1, 1964, effective April 1, 1965; amended through June 20, 1985, effective January 1, 1986 15 Pa.B. 2452; amended December 19, 2003, effective July 1, 2004, 34 Pa.B. 22. Immediately preceding text appears at serial page (213388).