Yes, You've inverted it.

Here's how it should be configured :

  That was it!  That returns the correct format : (2;#Item 2;#3;#Item 3)  It still doesnt seem to update the other column in List B though - still throws the primitive node error.              

ok, sorry, this means that this format was only for OnPrem (I haven't tested on O365).

Can you try with this format : [{"Id":5,"Value":"7"},{"Id":4,"Value":"Item 4"}] (only using

• "Replace Substring in String" to replace {"results": by nothing
• "Replace Substring in String" to replace }]} by }]

)

Hope it works

I set the workflow variable (which is a column in the current item - the reference for my lookup in List . Then O365 Update Item:

This results in an error:

Some parameters failed the validation check.

- [InputMetaDataXml] : The 'Fields to update' is invalid. Input string was not in a correct format.

I've been able to format it in this way:

[{"Id":3,"Value":"Item 3"},{"Id":4,"Value":"Item 4"}]

I still get the same primitive node error.  I've also tried with this formatting and achieved the same results.

>{"Id":2;#Item 2;#3;#Item 3"}]

Does this format need to be delimited with the ";#"  like this?

p{"Id":3,"Value":"Item 3"};#{"Id":4,"Value":"Item 4"}]

I have tried both formats:

{3};#{Item 3};#{4};#{Item 4}

3;#Item 3;#4;#Item 4

I still get the same error regardless of the format:

An unexpected 'PrimitiveValue' node was found when reading from the JSON reader. A 'StartObject' node was expected.

Same for:

{3};#{Item 3};#{4};#{Item 4}

3;#Item 3;#4;#Item 4

I still get the same error regardless of the format:

An unexpected 'PrimitiveValue' node was found when reading from the JSON reader. A 'StartObject' node was expected.

Anyone have any thoughts on how to approach this?  Really stuck in my project here - all help so far truly appreciated!

I've tried several format and nothing worked. You can do it with a post REST API web request but it should be possible to do it with the Update Item action. Maybe you should create a ticket and Nintex support will help you.

Does anyone know how to obtain the licensing and version info from Office 365 that's required to even open a case?  I only have a Tennant ID listed under Help/About.

Sorry - realize this isn't necessary: Please let us know your License key when you submit a support ticket, see Nintex Licensing Information for details on how to do this! (If you are on Nintex for Office 365, please leave the license ID field blank). This will help our team and expediate your submission, without having to get a call from one of our friendly Customer Service Reps .

However when submitting with a blank License Field - I still receive an error:

That's strange. Emily Billing do you have an idea ?

Figured it out she helped on another thread

Great

If you have any news from Nintex support, don't hesitate to share

So far they think this is an O365 bug - but definitely will keep the community informed.                                  

Great, thank you Jonathan

Support closed this ticket as a bug in SharePoint Online unfortunately and pointed me to this post:

Jason Lee's Blog: Getting and Setting Managed Metadata Fields in SharePoint 2013 Workflow

I'll give this a try and keep everyone updated.         

Thank you for this update. If you need help on building the requests to update the multi lookup field, don't hesitate !

Any idea whether this has been resolved yet?

I have not tried it since I posted this but I'd be curious if anyone has gotten it to work.

same issue i am facing i am not able to  Create item from a multiple lookup filed. Hence tried Web Request but the value i need is to be comma separated but the column value is like  {"results":s{"Id":5,"Value":"California"},{"Id":1,"Value":"Northeast"}]} but i need to parse it to 5,1  

Hi all , Very Happy to end this Thread, look in to this 

Great !

Thanks for your feedback !