Hi every one, ive done the latest Windows Update wich name is :

Im suspecting an error on Excel since last friday.
Error appear with Revit 2020, 2021, 2022. ( dynamo 2.3, 2.5 and 2.10)

Any suggestions ?

Hi @jonathan.riboud

You are accessing/writing a single file via 2 processes.
One of the two will surely throw an error.

Just use one process at a time.


Same error without csv export

hi @jonathan.riboud

According to my experience, that error occurs when the excel file is opened by another application or two or more Dynamo node is trying to access the same file.

Please make sure that there are no other application opens the excel file (not even Microsoft Excel) and only one node is saving the file.


Not in this case. Thank for your help @blsalvio . Have a nice day !

I think there’s a link with visual basic in the last microsoft Update.
But i don’t understand what.

Any suggestion for fixing this excel error ? @Kulkul @Alban_de_Chasteigner @solamour

Best regards

Hello Jonathan,

The following is a few tips from @Michael_Kirschner2 :

When you install office - make sure you select “.net programability” feature for excel see: How to: Install Office primary interop assemblies - Visual Studio | Microsoft Docs

If that does not work - try installing:
you should not need them - they should have been installed with excel… but this is worth a shot:
Download Microsoft Office 2010: Primary Interop Assemblies Redistributable from Official Microsoft Download Center

Otherwise, please have a read of this thread where Mike offers a few other suggestions: Import Excel Exception Could not load file or assembly 'Microsoft.Office.Interop.Excel, Version= · Issue #11632 · DynamoDS/Dynamo · GitHub

I found the solution with IT : make sure your 64 bit Office version correspond to your exploitation system (64bits).

In my case, excel run in 32 bits overwise windows is 64bit.

Once 32 bit version removed and the other Office
version installed, problem disappear.

Import and export data works both of them.

Best regards