FLC TOOK OFF WITH 1 AUTOPRESSURIZATION SYS INOP AND DEFERRED. IMMEDIATELY AFTER TKOF; #2 AUTOPRESSURIZATION SYS FAILED. RESETTING CIRCUIT BREAKER CURED THE PROB UNTIL APPROX FL310; AT WHICH TIME THE CABIN ALT WARNING SOUNDED. MANUAL OP WAS SELECTED FOR THE REMAINDER OF THE FLT.

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DURING PREFLT; FOUND #1 AUTOPRESSURIZATION CONTROLLER INOP. CALLED MAINT AND HAD SYS DEFERRED. AUTODEPRESSURIZATION #2 AND MANUAL SYS WERE OPERATING OK. IMMEDIATELY AFTER TKOF; THE #2 AUTOCONTROLLER FAILED TO PRESSURIZE THE CABIN. I WENT TO MANUAL CTL AND STARTED TO PRESSURIZE THE CABIN. AFTER RESETTING THE #2 AUTOCONTROLLER CIRCUIT BREAKER; THE SYS RESET AND BEGAN TO WORK. I RETURNED TO THE #2 SYS AND WE CONTINUED THE CLBOUT OF 10000 FT FOR FL330. AT APPROX FL310; THE CABIN ALT WARNING HORN WENT OFF. THE FO AND I DONNED OUR OXYGEN MASKS AND THEN I WENT BACK TO THE MANUAL MODE AND STARTED TO REPRESSURIZE THE CABIN. THE CABIN ALT REACHED ABOUT 10500 FT. AT ABOUT THIS TIME WITH EVERYTHING HAPPENING; DSNDING TO FL260; SILENCING THE WARNING HORN; TALKING TO ATC; TRYING TO TALK TO EACH OTHER IN THE COCKPIT; AND TRYING TO RUN CHKLISTS. I HAD NO EICAS MESSAGES ON THE AUTOPRESSURIZATION SYS BEING INOP AND ONLY A STATUS MESSAGE ON THE #1 SYS. I CALLED DISPATCH AND ADVISED THEM OF THE SIT. WE WERE ALREADY BEGINNING OUR DSCNT FOR ORD. THE REST OF THE FLT AND LNDG WERE UNEVENTFUL.