The template language expression xxx cannot be evaluated because property yyy doesn't exist

[PaulD1]

Hi

Whenever I try to create a Flow the uses multiple different connectors, I'm getting the error:

The template language expression xxx cannot be evaluated because property yyy doesn't exist

Steps to recreate below:

First I create a simple email flow

1. I create a Flow (triggered by PowerApps but I get the same in other triggers)
2. I add an Office 365 Outlook - send an email step
3. I test and all is well

Second I crate a simple project flow

1. I create a Flow triggered by PowerApps
2. I add a Project - List Tasks step
3. I test and all is well

Now I create a simple flow with both steps

1. I create a Flow triggered by PowerApps
2. I add a Project - List Tasks step
3. I test and all is well
4. I add an Office 365 Outlook - send an email step
5. I test and get the error in the subject heading

I have also tested with other combinations of services (e.g. SharePoint and Outlook, Project and SharePoint, Project and OneDrive) and all result in the same error.

Both the Project and the Email steps are using the same account name under My connections. 

Am I missing something fundamental? Any assistance appreciated!

Cheers

Paul

[PaulD1 · Accepted solution]

After more research it seems others may be experiencing similar issues intermittently.

I finally got my flows working by:

Repeatedly creating new Flows with just the steps connecting to the different services (e.g. Get Lists and Send Email) in the order required and only running/testing once all those steps were in place.

Next I added all of the other steps that don't connect to services (e.g. Data Operations) testing again as I added each.

Eventually I got a flow that works (until I want to add a new step which connects to a different service, at which point I expect to have to recreate the Flow again from scratch using the pattern described above).

What did not work was saving copies of flows and trying repeatedly to add a new service to an existing flow (e.g. I wanted to add the email step as the last step of an existing Flow).

I think there needs to be a 'recompile flow' option to clear out the invisible, obsolete garbage that gets added behind the scenes when steps are added but not removed when they are deleted...