# CPack + Wix + WixFirewallExtension - can I add a new xmlns to the filex.wxs file?

**URL:** https://discourse.cmake.org/t/cpack-wix-wixfirewallextension-can-i-add-a-new-xmlns-to-the-filex-wxs-file/1569
**Category:** Code
**Tags:** os:windows
**Created:** [July 16, 2020, 8:16am UTC](https://discourse.cmake.org/t/cpack-wix-wixfirewallextension-can-i-add-a-new-xmlns-to-the-filex-wxs-file/1569 "2020-07-16T08:16:39Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![bolz](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ce73a5/32.png) [@bolz](https://discourse.cmake.org/u/bolz)
#### Post date: [July 16, 2020, 8:16am UTC](https://discourse.cmake.org/t/cpack-wix-wixfirewallextension-can-i-add-a-new-xmlns-to-the-filex-wxs-file/1569/1 "2020-07-16T08:16:39Z")

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Hello,

I’m rather new at using CPack, so please bear with me.

I have a project for which I use CPack and Wix to create an msi. I need to add a firewall exception for the installed executable, but I get this error in **wix.log** :

```
files.wxs(23) : error CNDL0104 : Not a valid source file; detail: 'fire' is an undeclared prefix. Line 23, position 22. 

```

I think the solution would be to add the **xmlns:fire=“[http://schemas.microsoft.com/wix/FirewallExtension](http://schemas.microsoft.com/wix/FirewallExtension)”** attribute to the **Wix** element in **files.wxs** , but I don’t know if that is even possible.

Here’s what I have right now:

- In my **CMakeLists.txt** I added the extension and the patch file:

- In **patch.xml** I added the following:

- The generated **files.wxs** looks like this:

The error in **wix.log** states that ‘fire’ is an undeclared prefix, which I think would be solved by adding the appropriate xmlns attribute. Can that be done?

Thank you for taking the time to help me!

Bogdan

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### Author: ![Oleksii\_Moskalenko](https://discourse.cmake.org/user_avatar/discourse.cmake.org/oleksii_moskalenko/32/779_2.png) [@Oleksii\_Moskalenko](https://discourse.cmake.org/u/Oleksii_Moskalenko)
#### Post date: [August 4, 2020, 12:01pm UTC](https://discourse.cmake.org/t/cpack-wix-wixfirewallextension-can-i-add-a-new-xmlns-to-the-filex-wxs-file/1569/2 "2020-08-04T12:01:41Z")

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Hello,  
Just use **xmlns:fire** into **fire:FirewallException**  
like this

```
<CPackWiXFragment Id="CM_FP_myapp.exe">
    <fire:FirewallException xmlns:fire="http://schemas.microsoft.com/wix/FirewallExtension" Id="FWX1" Name="My App" Scope="any" />
</CPackWiXFragment>
```

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<div class="post-metadata">

### Author: ![bolz](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ce73a5/32.png) [@bolz](https://discourse.cmake.org/u/bolz)
#### Post date: [August 4, 2020, 12:08pm UTC](https://discourse.cmake.org/t/cpack-wix-wixfirewallextension-can-i-add-a-new-xmlns-to-the-filex-wxs-file/1569/3 "2020-08-04T12:08:56Z")

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Thanks for the answer, but I gave up on using CPack, as it didn’t seem to be all that useful in my case. I ended up just manually creating the `.wixproj` and then using `include_external_msproject` in `CMakeLists.txt`.