How to fix Dynamo Notifications about System.IO.FileLoadException?

FAQ
1

When ever I open Dynamo I keep getting this message, please could someone explain what why I have got this message?

While loading assembly DynamoMEP, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null, Dynamo detected that the dependency RevitAPI, Version=17.0.0.0, Culture=neutral, PublicKeyToken=null was already loaded with an incompatiable version. It is likely that another Revit Addin has loaded this assembly, please try uninstalling other Addins, and starting Dynamo again. Dynamo may be unstable in this state.
It is likely one of the following assemblies loaded the incompatible version:
UIFrameworkInterop, UIFrameworkInterop, UIFrameworkInterop, UIFramework, UIFramework, UIFrameworkServices, AddInManagerUI, AddInManagerUI, APIInterop, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, RevitAPI, GeomUtilAPI, GeomUtilAPI, GeomUtilAPI, GeomUtilAPI, UtilityAPI, RevitDBAPI, RevitDBAPI, RevitDBAPI, RevitDBAPI, RevitDBAPI, RevitDBAPI, FamilyDBAPI, FamilyDBAPI, FamilyDBAPI, FamilyDBAPI, FamilyDBAPI, FamilyDBAPI, EssentialsDBAPI, EssentialsDBAPI, EssentialsDBAPI, EssentialsDBAPI, EssentialsDBAPI, EssentialsDBAPI, GraphicsAPI, GraphicsAPI, RoomAreaPlanDBAPI, RoomAreaPlanDBAPI, RoomAreaPlanDBAPI, RoomAreaPlanDBAPI, RoomAreaPlanDBAPI, ArrayElemsDBAPI, ArrayElemsDBAPI, ArrayElemsDBAPI, ArrayElemsDBAPI, ArrayElemsDBAPI, StructuralDBAPI, StructuralDBAPI, StructuralDBAPI, StructuralDBAPI, StructuralDBAPI, StructuralDBAPI, HostObjDBAPI, HostObjDBAPI, HostObjDBAPI, HostObjDBAPI, HostObjDBAPI, HostObjDBAPI, SculptingDBAPI, SculptingDBAPI, SculptingDBAPI, SculptingDBAPI, SculptingDBAPI, ElementGroupDBAPI, ElementGroupDBAPI, ElementGroupDBAPI, ElementGroupDBAPI, CurtainGridFamilyDBAPI, CurtainGridFamilyDBAPI, CurtainGridFamilyDBAPI, CurtainGridFamilyDBAPI, SiteDBAPI, SiteDBAPI, SiteDBAPI, SiteDBAPI, SiteDBAPI, DetailDBAPI, DetailDBAPI, DetailDBAPI, DetailDBAPI, DetailDBAPI, BuildingSystemsDBAPI, BuildingSystemsDBAPI, BuildingSystemsDBAPI, BuildingSystemsDBAPI, BuildingSystemsDBAPI, BuildingSystemsDBAPI, BuildingSystemsDBAPI, EnergyAnalysisDBAPI, EnergyAnalysisDBAPI, EnergyAnalysisDBAPI, AnalysisAppsDBAPI, AnalysisAppsDBAPI, AnalysisAppsDBAPI, AnalysisAppsDBAPI, StructuralAnalysisDBAPI, StructuralAnalysisDBAPI, StructuralAnalysisDBAPI, StructuralAnalysisDBAPI, StructuralAnalysisDBAPI, StructuralAnalysisDBAPI, RebarDBAPI, RebarDBAPI, RebarDBAPI, RebarDBAPI, RebarDBAPI, AssemblyDBAPI, AssemblyDBAPI, AssemblyDBAPI, AssemblyDBAPI, APIDBAPI, APIDBAPI, APIDBAPI, APIDBAPI, APIDBAPI, APIDBAPI, DPartDBAPI, DPartDBAPI, DPartDBAPI, DPartDBAPI, StairRampDBAPI, StairRampDBAPI, StairRampDBAPI, StairRampDBAPI, StairRampDBAPI, InterfaceUtilAPI, InterfaceUtilAPI, InterfaceUtilAPI, InterfaceUtilAPI, InterfaceUtilAPI, InterfaceUtilAPI, InterfaceAPI, InterfaceAPI, PointCloudAccessAPI, PointCloudAccessAPI, NumberingDBAPI, NumberingDBAPI, NumberingDBAPI, NumberingDBAPI, MassingDBAPI, MassingDBAPI, MassingDBAPI, MassingDBAPI, RevitAPIIFC, RevitAPIIFC, RevitAPIIFC, RevitAPIIFC, RevitAPIIFC, IntfIFCAPI, IntfIFCAPI, AddInManager, AddInManager, AddInManager, KeynoteDBServer, StraightSegmentCalculationServers, FittingAndAccessoryCalculationServers, CollaborateDB, CollaborateDB, CollaborateDB, CollaborateDB, Revit.IFC.Export, Revit.IFC.Export, Revit.IFC.Import, Revit.IFC.Import, RSCloudClient, RSCloudClient, RSCloudClient, AddInJournaling, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, RevitAPIUI, BuildingSystemsUIAPI, BuildingSystemsUIAPI, BuildingSystemsUIAPI, BuildingSystemsUIAPI, RevitUIAPI, RevitUIAPI, RaaSApplication, RaaSApplication, RaaSApplication, RaaSApplication, RaaSApplication, RaaSApplication, RaaSApplication, RaaSApplication, AutoLoader, AutoLoader, FabricationPartBrowser, FabricationPartBrowser, FabricationPartBrowser, FabricationPartBrowser, FabricationPartBrowser, FittingAndAccessoryCalculationUIServers, FittingAndAccessoryCalculationUIServers, FittingAndAccessoryCalculationUIServers, KeynoteUIServer, KeynoteUIServer, MemberForces, MemberForces, MemberForces, ObjectNumberingUI, ObjectNumberingUI, ObjectNumberingUI, PressureLossReport, PressureLossReport, SectionProperties, SectionProperties, SectionProperties, SectionProperties, AlignTag, AlignTag, Collaborate, Collaborate, Collaborate, Collaborate, Collaborate, Collaborate, Collaborate, CollaborateBrowser, CollaborateBrowser, CollaborateBrowser, CollaborateBrowser, CollaborateBrowser, SkyscraperClientHost, SkyscraperClientHost, SkyscraperClientHost, SkyscraperClientHost, C4RNET, C4RNET, C4RNET, eTransmitForRevit, eTransmitForRevit, eTransmitForRevit, AREXRevitStart, AREXRevitStart, SpaceNaming, SpaceNaming, AutodeskSiteDesignerForRevit2016, AutodeskSiteDesignerForRevit2016, AutodeskSiteDesignerForRevit2016, BIM360GlueRevit2016Addin, BIM360GlueRevit2016Addin, BIM360GlueRevit2016Addin, BIM360GlueRevit2016Addin, SSONETUI, SSONETUI, SSONET, SSONET, COBieExtension2016, COBieExtension2016, COBieExtension2016, CoinsSectionBoxApp2016, CoinsSectionBoxApp2016, SmartMonkey, SmartMonkey, SmartMonkey, DynamoRevitVersionSelector, DynamoRevitVersionSelector, Dyno, Dyno, DynoUI, EADigiParaLoader.2016, EADigiParaLoader.2016, ExcelExporterImporter, ExcelExporterImporter, ExportViewSelectorAddin, ExportViewSelectorAddin, IdeateSoftwareISW, IdeateSoftwareISW, IdeateBIMLink, IdeateBIMLink, IFCExportUIOverride, IFCExportUIOverride, IFCExportUIOverride, Revit.IFC.Common, Revit.IFC.Common, nwexportrevit2016_13, nwexportrevit2016_13, RevitLookup, RevitLookup, AcRVTDWGCoordsSyncRevitClient, AcRVTDWGCoordsSyncRevitClient, RevitAPIUIMacrosInterop, RevitAPIUIMacrosInterop, RevitAPIMacrosInterop, RevitAPIMacrosInterop, RevitAPIMacrosInterop, AddInJournalClient, REX.ApplicationServices, AREXRevitMngr, AREXRevitMngr, DReinfBeam, DReinfBeam, REX.Foundation.Forms, REX.Foundation.Forms, REX.Reinforcement, REX.Geometry, DReinfColumn, DReinfColumn, DReinfFootingSpread, DReinfFootingSpread, DReinfWall, DReinfWall, RSEnterpriseClientInterop, RSEnterpriseClientInterop, RSEnterpriseClientInterop, RSEnterpriseClientInterop, RSEnterpriseClientInterop, RSEnterpriseClientInterop, RSEnterpriseClient, RSEnterpriseClient, RSEnterpriseClient, RSEnterpriseClient, RSEnterpriseClient, RSEnterpriseClient, RevitAPIBrowserUtils, RevitAPIBrowserUtils, RevitAPIBrowserUtils, RevitAPIBrowserUtils, MacroHookup, MacroHookup, DynamoRevitDS, DynamoRevitDS, RevitServices, RevitServices, DynamoRaaSHelper, RevitNodes, RevitNodes, SimpleRaaS, SimpleRaaS, RevitRaaS, RevitRaaS, RevitRaaS, RevitRaaS, RevitRaaS, RevitRaaS, RevitRaaS, DSRevitNodesUI, DSRevitNodesUI, DynamoRaaS, archilabTypes, archilabUI

2

Hi Ben,
Looks like you have more than one Dynamo version installed in your system. Try unistalling all the versions and then re-install the latest version.

1 Like
3

Kulkul,

Thanks for you help.

Spend some time looking into this problem and it seem that the DynamoMEP package is creating this problem. I don’t know why it creating this problem but it would be great if they can fix it.

I really like their nodes.

Ben

4

seems like they might be distributing a version of the revit api .dlls? Look in their bin folder inside the package and see if there is something included that is already loaded when Dynamo starts, for instance like RevitAPI.dll

5

Yes they do have their own .dlls shown in the image below.

How would you solved that problem?

6

This suggestion worked for me. I only had to uninstall versions before 1.2.1 and reinstall 1.3.

7

I am having a similar problem, but I would like to keep both 1.3.x and 2.x versions.
I have no other versions installed.

Is there a good way for me to debug which packages are causing it?

Thank you

8

Any Fix for this yet?

10

So I deleted the post because found the solution :

Had the same problem in Revit 2022 but had to do with Rhythm package that was cause the same message.
Found it in detailed description, deleted the package and installed the latest version.