Narrative:

[After departure]; upon retraction of the landing gear the amber message 'cabin door' came on. I was the pilot flying. At safe altitude and autopilot engaged I called for the checklist and took over the radio. After asking to level off at 5;000 ft; we noticed that the cabin rate matched the rate of climb of the airplane; which prompted me to shallow out the climb. We agreed that the safest course of action was to return to [departure airport]. I asked for delay vectors; as we were about 600 lbs overweight; and 3;000 ft with probable return to the field. The first officer briefed the [passengers] on the dynamics of the situation. After transferring controls; I called the [chief pilot] on duty and described the predicament. He agreed on the plan of action and started the recovery process. I then called [FBO] to alert them of our arrival. Upon reaching max landing weight we were turned to final on a visual. Landing was uneventful although the ground air brakes did not deploy. We assisted the [passengers] until the recovery crew came from the hotel. They never showed any concern and were very polite in the interaction with us and the next crew.

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Original NASA ASRS Text

Title: G-200 fractional Captain reported noting after takeoff they got a 'CABIN DOOR' warning and the aircraft did not pressurize. Flight returned to departure airport.

Narrative: [After departure]; upon retraction of the landing gear the amber message 'cabin door' came on. I was the pilot flying. At safe altitude and autopilot engaged I called for the checklist and took over the radio. After asking to level off at 5;000 ft; we noticed that the cabin rate matched the rate of climb of the airplane; which prompted me to shallow out the climb. We agreed that the safest course of action was to return to [departure airport]. I asked for delay vectors; as we were about 600 lbs overweight; and 3;000 ft with probable return to the field. The First Officer briefed the [passengers] on the dynamics of the situation. After transferring controls; I called the [Chief Pilot] on duty and described the predicament. He agreed on the plan of action and started the recovery process. I then called [FBO] to alert them of our arrival. Upon reaching max landing weight we were turned to final on a visual. Landing was uneventful although the ground air brakes did not deploy. We assisted the [passengers] until the recovery crew came from the hotel. They never showed any concern and were very polite in the interaction with us and the next crew.

Data retrieved from NASA's ASRS site as of July 2013 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.