Try unplugging all the receivers, and the power inserter for a minute or so.
Also, double check the switch input connections. 1a/1b should go to the 119 LNBF, 2a/2b to the 110 LNBF and 3a/3b to the 61.5/148 LNBF in that order.
If the receivers still fail the switch check, and ~24V is...