Whoah! Too bad that I read this 1 year too late!
In a CALIFORNIA unlawful detainer action for residential property, service of summons and complaint by posting is illegal unless the plaintiff has first received permission from the court to do so. I am not sure if this applies to commercial property.
Example: If the process server shows up on 3 separate occasions and cannot find a responsible adult, then the landlord must first petition the court for the right to post the notice on the door.
Please note that the landlord must have served the tenant a 3-day notice first, either
*in person
OR
*by posting on the door (without permission from the court, of course) and then mailing a copy to EACH tenant.
There you have it.

