Issue with “Block Until Done” and Multiple Output Data Tools Writing to Same File

[JavidanZ]

Hello Alteryx Community,

I’m facing an issue with the Block Until Done tool. My workflow uses three Output Data tools that all write to the same Excel file. I added Block Until Done to ensure sequential execution, but I still get errors.

Expected:
Each Output Data tool writes to the file one after another without conflict.

Actual:
I receive the following error:
Can't open file: \\path\RTR_SAP_MJEs_PES_2025-09.xlsx. The process cannot access the file because it is being used by another process (32).

Details:

• File type: Excel (.xlsx)
• AMP engine: Enabled
• Output mode: Overwrite existing sheet

Has anyone experienced this? Is there a better way to handle multiple writes to the same file?

[JosephSerpis]

Hi @JavidanZ if you have Designer 2023.1+ then you have access to Control Containers which control the order of execution. You could put your output data tools in separate control containers and link them together so they output in sequence. 

[MelGibson]

Controlled Containers one of the best upgrades with Alteryx. Makes my life so much easier. 

[abacon]

@JavidanZ In agreement with everyone on here, yes control containers are amazing.

However, if you don't have access to them, and just as a general note. I found block until done tools don't work like you expect when AMP engine is turned on. If you turn of AMP engine and re-run, that should clear your error without using control containers.

But best practice would be to use control containers.

Bacon

[dreldrel]

I think you only need one block until done tool to achieve your current workflow instead of three