This typically means that there is a problem with the .flt file that was opened. First try downloading our featured download from the community page and open it. Featured downloads are tested and known to be good flight plans, you can download the current one here http://simflightplan.com/staging/series/featured/.
If you modified a working flight plan and now are unable to open it, the most common reason is punctuation in the waypoints or descriptions. Waypoints are stored as comma delimited strings and also has special punctuation that Microsoft Flight Simulator can regonize when loading the flight plan. Likewise, Flightplan must be able to parse the waypoints in the same way that MSFS does and will throw a “Flight plan cannot be read” error if it encounters an unexpected character in an invalid place. It is advisable not to use the following characters in your waypoint names or descriptions:
- colon :
- semicolon ;
- comma ,
It is also possible that invalid data was entered in one of the parameter values. Flightplan reads and loads all of the data it can find in the flight file and displays the values in the appropriate fields on the Flight Settings, Fuel Tanks, Aircraft Settings, etc. forms. It possible to have “bad” values in the flight or aircraft parameters that could prevent the file from being read. For example, if a value should be numeric and an alphabetical character is entered it is possible the flight file may not open. That said, the file will not load in MSFS either, any flight file that MSFS can load should be readable by Flightplan. So if you started with a flight plan from World Map and made changes to it, you may have to recreate the flight file in World Map again and start over (or edit the .flt text file manually).
If you are unable to open the featured flight plan or believe that you’ve received this message on a valid flight plan, please contact support at http://simflightplan.com/staging/support/.