B777 Doesnt climb using Vnav

[ThreeGreens 7]

Hi,Fs2004Fresh install.When I program the CDU and set up a flight, line up select FD and LNAV/VNAV they light up. but when I lift off and engage them the nose comes back down and it levels off never climbing to my set alt...Any ideas?Scott

[rservice 4]

Check your flight plan for altitudes at selected waypoints.Also is your mcp set for your max programmed altitude.Some flight plans limit altitude to say 5000 feet until past certain waypoints. Ron

[ubersu 78]

Make sure your next desired altitude is set in the MCP and after engaging the autopilot, push the altitude setting button. The MCP acts to override whatever is set in the CDU.DJ