Outlook NodeApiError: were unable to deserialize

[olivier_sabban]

Hello everyone,

I’m currently facing an issue when posting a message on n8n (cloud version) and adding an attachment to Outlook (also cloud version). I’m encountering a “NodeApiError: were unable to deserialize” error each time I attempt to include an attachment. I’ve confirmed that the binary data is being correctly retrieved, and I’m using the correct variable name for the attachment. However, the error persists. Has anyone encountered a similar issue or have any insights on how to resolve this?

Thank you in advance for your help!

[n8n]

It looks like your topic is missing some important information. Could you provide the following if applicable.

• n8n version:
• Database (default: SQLite):
• n8n EXECUTIONS_PROCESS setting (default: own, main):
• Running n8n via (Docker, npm, n8n cloud, desktop app):
• Operating system:

[olivier_sabban]

• Running n8n via (Docker, npm, n8n cloud, desktop app): n8n cloud
• n8n version: 1.29.1
• Database (default: SQLite): -
• n8n EXECUTIONS_PROCESS setting (default: own, main): -
• Operating system: -

Thank you in advance for your help!

[Jon]

Hey @olivier_sabban,

Welcome to the community

I have just given this a quick go and have managed to reproduce it and have created NODE-1223 as the internal ticket to get this fixed.

[nitodeco]

Hi @Jon,

I am currently facing the same issue on n8n cloud version 1.45.1. Has the issue been fixed in a newer version? Unfortunately I couldn’t find anything related on GitHub. Thanks for looking into it!

[Crazydarkman13]

Same, unable to deserialize error. This is a quite a setback as the msft set meeting node has no option to add attendees and I have to use HTTP node which now produces this error. Stuck.
HTTP Node version
4.2 (Latest)
n8n version
1.75.2 (Cloud)

[J_Oppus]

here with same request. can n8n already fix this please?

[bvoi]

I am facing the same issue with being unable to deserialize attachments with the Outlook node. This is a super important feature for me. Thanks for your help!

[AzureAgentDev]

Experiencing the same issue trying to add an attachment to an email usong the outlook node

[alfonsotfp]

Hi! Having the same issue here. Any updates??

[RMElevate]

Same here!

[peter_eliades]

the problem still exists

[cass-logic2020]

Also receiving the same issue when trying to attach an image to the outlook message.

[Automationpeasant]

Problem still exists for me as well, any update on this?

[p-krukenfellner]

Any intention to fix this? This has been a known issue for quite some time now.

[HR_Immo]

I still have the same problem when trying to attach files via the Outlook node in the cloud version. Does anyone have a workaround for this?

[LucBerge]

Hey,

The main difference I see is the way `attachments` field is created for the message object:

• Send message: uses a for loop
• Create draft message: uses a Promise.all

In theory, the Promise.all will do the same as the for loop but can some try with a for loop instead ?

Also body.attachments is not defined as IDataObject[] but is by default object[]. It does not implement the correct interface.

This can cause to use the wrong serialization method leading to error when Microsoft deserialize the request:

{ "error": { "code": "UnableToDeserializePostBody", "message": "were unable to deserialize " } }

@Jon can you check and confirm ?

Edit: Add attachment node also fails, probably because data is not defined as `IDataObject` too…

[Ryan_Winkler]

Any updates on this issue? Seems to have been an open issue for well over a year now.

[LucBerge]

@Ryan_Winkler

been an open issue for well over a year

This is a widly known issue since a while : Search results for 'deserialize' - n8n Community

Can someone from N8N check my comment above please ?