GanttProject .Gan to Omniplan Failed

Hi
I cannot succeed to take my ganttprojet .gan file to omniplan

Here is the omniplan error:

2024-07-26 08:50:47.983 MSPXMLFilterXPCService[21208:314776] MSPIXMLImporter: Importing XML (MSPDI) file to OP 2 document bundle…
2024-07-26 08:50:47.983 MSPXMLFilterXPCService[21208:314776] Input: ‘/Users/mattao/Documents/GanttProject/Planning des travaux du FARE METUA-V1.xml’
2024-07-26 08:50:47.983 MSPXMLFilterXPCService[21208:314776] Output: ‘/Users/mattao/Library/Containers/com.omnigroup.OmniPlan3.MSPXMLFilterXPCService/Data/tmp/Planning des travaux du FARE METUA-V1.oplx’
2024-07-26 08:50:47.984 MSPXMLFilterXPCService[21208:314776] Begin loading XML document …
2024-07-26 08:50:47.992 MSPXMLFilterXPCService[21208:314776] Process XML DOM …
2024-07-26 08:50:47.996 MSPXMLFilterXPCService[21208:314776] The main base calendar found at UID(1)
2024-07-26 08:50:47.997 MSPXMLFilterXPCService[21208:314776] Total 1 resources found.
2024-07-26 08:50:47.997 MSPXMLFilterXPCService[21208:314776] Mapping Resource UID=1 name=‘’ …
2024-07-26 08:50:47.997 MSPXMLFilterXPCService[21208:314776] Total 6 assignments found.
2024-07-26 08:50:47.997 MSPXMLFilterXPCService[21208:314776] Total 67 task(s) found.
2024-07-26 08:50:47.998 MSPXMLFilterXPCService[21208:314776] Mapping Task(UID=0): …
2024-07-26 08:50:47.998 MSPXMLFilterXPCService[21208:314776] effort=(null) duration=PT3408H0M0S start=2024-02-22T08:00:00 finish=2025-04-22T17:00:00
2024-07-26 08:50:47.998 MSPXMLFilterXPCService[21208:314776] *** Assertion failure in -[MSPIProjectMapper buildMspTasks:assignmentMap:scenario:topGroupTask:error:], MSPIProjectMapper.m:729
2024-07-26 08:50:47.998 MSPXMLFilterXPCService[21208:314776] Exception: NSInternalInconsistencyException
This does not seem like a MS Project root task.
{
NSAssertFile = “MSPIProjectMapper.m”;
NSAssertLine = 729;
}
2024-07-26 08:50:47.998 MSPXMLFilterXPCService[21208:314776] ### Importer FAILED.

Please HELP

Provided that you exported the project from GanttProject to MS Project XML format and you RE trying to import the MS Project file into Omniplan, it makes more sense to contact Omniplan developers first.

Hello

I do not own an omniplan licence so I cannot use this method.

Nevertheless:

I succeed to open the file with:Project Viewer for Google Drive

I downloaded back the file in xml

It was a success.

Hope it will help someone else