# Blocking Step in the loop

**URL:** <https://community.automationedge.com/t/blocking-step-in-the-loop/2151>\
**Category:** Get Help & Discuss\
**Created:** [May 29, 2020, 9:47am UTC](https://community.automationedge.com/t/blocking-step-in-the-loop/2151 "2020-05-29T09:47:43Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kunal](https://avatars.discourse-cdn.com/v4/letter/k/dec6dc/32.png) [@kunal](https://community.automationedge.com/u/kunal)\
**Post date:** [May 29, 2020, 9:47am UTC](https://community.automationedge.com/t/blocking-step-in-the-loop/2151/1 "2020-05-29T09:47:43Z")

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Why Can’t we use the blocking step in the loop?

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**Author:** ![rohini.deshpande](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@rohini.deshpande](https://community.automationedge.com/u/rohini.deshpande)\
**Post date:** [May 29, 2020, 11:01am UTC](https://community.automationedge.com/t/blocking-step-in-the-loop/2151/2 "2020-05-29T11:01:15Z")

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Hi Kunal,

The Blocking step blocks all output until the very last row is received from the previous step. And it passes all rows at a time to the next step.  
Whereas loop concept is a single threaded concept. It allows only one row at a time to pass through the loop or enter into the loop region. So if we try to use a Blocking step inside the loop, it will block the execution of the loop block/region. Which will create an error in the execution of the loop.