After downloading the new updated sl viewer 2.8 my new lingen home entrance doors will not unlock .

[rabbitboo]

The doors to the linden home will no longer unlock  from the entrance doors or the interior control panel.

[valerie Inshan]

OK, so it's another V2 bug. File a ticket:

https://support.secondlife.com/create-case/

And in the meantime, revert to an older version:

https://support.secondlife.com/create-case/

or use a TPV:

http://www.phoenixviewer.com/downloads.php

[Faubio Alter]

Contact the SIM owner about this and request a SIM restart (hang in server, server glitch) or simple remove the door and install a new one.  More then likely it is corrupted (remove and replace).