# Onebox error code of 403

**URL:** <https://meta.discourse.org/t/onebox-error-code-of-403/189000>\
**Category:** Product Support\
**Created:** [May 3, 2021, 2:00pm UTC](https://meta.discourse.org/t/onebox-error-code-of-403/189000 "2021-05-03T14:00:25Z")\
**Posts on this page:** 1\
**Showing post:** 1

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**Author:** ![SkyLin](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/skylin/32/206593_2.png) [@SkyLin](https://meta.discourse.org/u/SkyLin)\
**Post date:** [May 3, 2021, 2:00pm UTC](https://meta.discourse.org/t/onebox-error-code-of-403/189000/1 "2021-05-03T14:00:25Z")

</div>

The preview function of Onebox for udemy url got an error as below.

“Sorry, we were unable to generate a preview for this web page, because the web server returned an error code of 403.”

Not sure if it’s due to the discourse updating today or the site itself. Here comes the situation.

1. The udemy site preview works fine before yesterday. Sample url:  
[Udemy free coupon code 2021\_0502-2 - udemy 優惠券 - StudyCamp 線上學習論壇](https://vip.studycamp.tw/t/topic/1370)

2. The Onebox preview doesn’t work today. Sample url:  
[Udemy free coupon code 2021\_0503 - udemy 優惠券 - StudyCamp 線上學習論壇](https://vip.studycamp.tw/t/topic/1379)

I did some further testing.

1. youtube Onebox preview works fine

2. udemy preview on facebook debug tool works fine  
[https://developers.facebook.com/tools/debug/](https://developers.facebook.com/tools/debug/)

Sample udemy course url for testing: (Weird, the preview works fine here)  
[https://www.udemy.com/course/ultimate-devsecops-with-real-world-scenarios/?couponCode=AGER4U](https://www.udemy.com/course/ultimate-devsecops-with-real-world-scenarios/?couponCode=AGER4U)

Please advice. Thanks a lot!

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