# ERROR: cannot launch node of type \[exercise\_23/publish\_age.py\]: can't locate node \[publish\_age.py\] in package \[exercise\_23\]

**URL:** <https://get-help.theconstruct.ai/t/error-cannot-launch-node-of-type-exercise-23-publish-age-py-cant-locate-node-publish-age-py-in-package-exercise-23/2304>\
**Category:** ROS Basics In 5 Days (Python)\
**Created:** [February 16, 2020, 9:13pm UTC](https://get-help.theconstruct.ai/t/error-cannot-launch-node-of-type-exercise-23-publish-age-py-cant-locate-node-publish-age-py-in-package-exercise-23/2304 "2020-02-16T21:13:36Z")\
**Posts on this page:** 1\
**Showing post:** 3

<div class="post-metadata">

**Author:** ![bayodesegun](https://get-help.theconstruct.ai/user_avatar/get-help.theconstruct.ai/bayodesegun/32/10684_2.png) [@bayodesegun](https://get-help.theconstruct.ai/u/bayodesegun)\
**Post date:** [February 17, 2020, 10:26am UTC](https://get-help.theconstruct.ai/t/error-cannot-launch-node-of-type-exercise-23-publish-age-py-cant-locate-node-publish-age-py-in-package-exercise-23/2304/3 "2020-02-17T10:26:10Z")

</div>

Hi @steve26,

Welcome to the Community!

As @simon.steinmann91 mentioned, it’s probably an execute permisssion issue. The full reference to this error can be found in this knowledgebase post:

> **[ERROR: cannot launch node of type \[package/file.py\]: can't locate node...](https://get-help.theconstruct.ai/t/error-cannot-launch-node-of-type-package-file-py-cant-locate-node-file-py-in-package-package/54)**
>
> This error is very common when using ROS to launch a python node, either via rosrun or roslaunch. SOLUTION: Does the file file.py… exist in the package package? If not, create it! (Does the package itself exist and is it spelled correctly?)....

---

_[View the full topic](https://get-help.theconstruct.ai/t/error-cannot-launch-node-of-type-exercise-23-publish-age-py-cant-locate-node-publish-age-py-in-package-exercise-23/2304)._