Dispatcher reported a B777 failed to pressurize resulting in a return to departure airport.

Attributes
ACN	1683128
Time
Date	201909
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	B777-200
Operating Under FAR Part	Part 121
Flight Phase	Initial Climb
Flight Plan	IFR
Component
Aircraft Component	Service/Access Door
Person 1
Function	Dispatcher
Qualification	Dispatch Dispatcher
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy

Narrative:

Fuel dump due [to a] pressurization issue [since the] aircraft would not pressurize. Flight leveled off at FL100 to work [on] the issue. 94;000 lbs [of] fuel dumped for a return to ZZZ. An access door under nose [was] not secure [and] aircraft would not pressurize [as a result].

Original NASA ASRS Text

Title: Dispatcher reported a B777 failed to pressurize resulting in a return to departure airport.

Narrative: Fuel dump due [to a] pressurization issue [since the] aircraft would not pressurize. Flight leveled off at FL100 to work [on] the issue. 94;000 lbs [of] fuel dumped for a return to ZZZ. An access door under nose [was] not secure [and] aircraft would not pressurize [as a result].

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.