# No internet connection for Pinnacle 21 Community.

**URL:** <https://forum.certara.com/t/no-internet-connection-for-pinnacle-21-community/1974>\
**Category:** Troubleshooting and Problems\
**Created:** [October 24, 2023, 12:23am UTC](https://forum.certara.com/t/no-internet-connection-for-pinnacle-21-community/1974 "2023-10-24T00:23:27Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Matt\_Myers](https://sea1.discourse-cdn.com/certara/user_avatar/forum.certara.com/matt_myers/32/2548_2.png) [@Matt\_Myers](https://forum.certara.com/u/Matt_Myers)\
**Post date:** [October 25, 2023, 2:38pm UTC](https://forum.certara.com/t/no-internet-connection-for-pinnacle-21-community/1974/1 "2023-10-25T14:38:50Z")

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Hello Jongwon,

This is often seen when there are firewall rules in place on the machine. To ensure firewall restrictions are not the cause, feel free to email [community@pinnacle21.com](mailto:community@pinnacle21.com) so that we can provide you with a list of domains that should be whitelisted on the firewall.

Kind regards,

Matt

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**Author:** ![jwkim0517\_1](https://avatars.discourse-cdn.com/v4/letter/j/c2a13f/32.png) [@jwkim0517\_1](https://forum.certara.com/u/jwkim0517_1)\
**Post date:** [October 24, 2023, 12:23am UTC](https://forum.certara.com/t/no-internet-connection-for-pinnacle-21-community/1974/2 "2023-10-24T00:23:27Z")

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Even though my ethernet works fine, my P21 Community program shows ‘No Internet connection’ above.

Is there anyone who could help me?

I think this causes some define-xml errors…

I really appreciate any help you can provide.

 !["No internet connection" message on my P21C.png](https://us1.discourse-cdn.com/certara/original/1X/f3fd4520bd1a9907f83e7f2e9ce4d26501cf6f92.png)