Hello,Ever when I contact the Center controller, I get the instruction, to fly a heading, because I am not on the Airway. I flying with a FMC and so I use LNAV to fly the Route.The Problem is, that this heading not fit to my route.any idea?thanks

Some things come to my mind:First off do your flight plans created for FS9 and how you programmed the route in your FMC agree. What aircraft model are you using.When flying and before you get this error, look in the RC window and on your FMC LEGS window to see if they agree on the next waypoint and also the predicted heading.You need to be sure that you are getting credits for the waypoints in the RC plan. If you miss a waypoint RC will want you to return to it. If you want RC to advance to the next waypoint see the Direct Checkpoint option of the extended menu 9 option. Be sure if there are any RC altitude restrictions you meet them to get credit.If you are using a DP (SID) in the FMC this may not agree with the plan you filed from FS9. FMCs have their own DEP/STAR databases. ATC rules so make sure again your plans are in synch. If you use an external flightplanner to export the plan to the FMC and FS9 and a DP is exported from the planner and then you load a DP from the FMC database, they will probably not agree. So . . .Know how to do direct to waypoints in the FMC.If you want to fly an FMC based departure know what that departure route is and make sure the exit waypoint is in your FS9 plan. The read up on the RC instructions for choosing a departure without restrictions. You will not be held to departure points nor vectored.If you are being vectored on departure (using your MCP HDG) toward your enroute airway merge and you enage LNAV it will steer you toward the original path displayed on your ND. RC at this time expects you to fly direct to the next waypoint, not return to the original path LNAV expects. If the next checkpoint RC wants you to use (shown in the RC window) is on the LEGS page, LSK that point on the FMC then LSK the top line on page 1 of the LEGS page and that will place the indicated waypoint at the top and LNAV will take you there (don't forget to EXE the change). The FMC next waypoint heading should agree then with the RC heading and you will also note on the ND your path will now be direct from your present position.On some legs over 200 nm or so, there can be a difference between a great circle route and a linear FS type. In the options page of RC you can incease the allowable heading deviation a bit.These comments on FMC operation are based on my experience with the PMDG 737NGs but should be similar for other Boeings and loosely interpreted for even an Airbus. In general since ATC rules, know how to manipulate the FMC legs and when to engage and disengage LNAV and VNAV to direct your aircraft as instructed. Also in RC get to know the NOTAMS option which during departure and arrival get the controllers to ignore your method of getting to plan waypoints (but you still have to get credit or use the RC direct function).Hope this helps.