# Problem installing extension

**URL:** <https://www.ruby-forum.com/t/problem-installing-extension/103808>\
**Category:** Radiant CMS\
**Created:** [May 10, 2007, 3:24pm UTC](https://www.ruby-forum.com/t/problem-installing-extension/103808 "2007-05-10T15:24:15Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![commander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/df705f/32.png) [@commander](https://www.ruby-forum.com/u/commander)\
**Post date:** [May 10, 2007, 3:24pm UTC](https://www.ruby-forum.com/t/problem-installing-extension/103808/1 "2007-05-10T15:24:15Z")

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Hi,

I have just updated my radiant gem to the latest version. Then I  
created a new application which works fine so far. Then I installed  
the Gallery Extension from [http://darcs.bigchieflabs.com/radiant/](http://darcs.bigchieflabs.com/radiant/)  
extensions/gallery/rdoc/, following the instructions. But when I call  
rake radiant:extensions:gallery:install, I get the following error:

rake aborted!  
uninitialized constant AppExtension

I have no idea what’s going on. Any hint how to debug?

regards,  
Achim

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**Author:** ![commander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/df705f/32.png) [@commander](https://www.ruby-forum.com/u/commander)\
**Post date:** [May 11, 2007, 12:36pm UTC](https://www.ruby-forum.com/t/problem-installing-extension/103808/2 "2007-05-11T12:36:05Z")

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I’ll try the gallery extension with the latest version of radiant  
asap…let me know if you find the bug!!!  
thank you 😉

Il giorno 10/mag/07, alle ore 15:21, Achim D. ha scritto:

> I have no idea what’s going on. Any hint how to debug?
> 
> regards,  
> Achim
> 
> * * *
> 
> Radiant mailing list  
> Post: removed\_email\_address@domain.invalid  
> Search: [http://radiantcms.org/mailing-list/search/](http://radiantcms.org/mailing-list/search/)  
> Site: [http://lists.radiantcms.org/mailman/listinfo/radiant](http://lists.radiantcms.org/mailman/listinfo/radiant)

* * *

Andrea F.

removed\_email\_address@domain.invalid  
[http://bigchieflabs.com/blog/](http://bigchieflabs.com/blog/)  
[http://think.bigchief.it](http://think.bigchief.it)

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<div class="post-metadata">

**Author:** ![commander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/df705f/32.png) [@commander](https://www.ruby-forum.com/u/commander)\
**Post date:** [May 11, 2007, 4:57pm UTC](https://www.ruby-forum.com/t/problem-installing-extension/103808/3 "2007-05-11T16:57:42Z")

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Generally, when you run into the unintialized constant \_\_\_Extension  
error, it means a directory is misnamed. The reason for this is  
Radiant takes the directories under vendor/extensions one by one and  
transforms them into class names like so:

fuzzy\_bears =\> FuzzyBearsExtension  
page\_attachments =\> PageAttachmentsExtension

This is how Radiant finds the extension file and class. That said, I  
suspect you checked out/exported the extension directly into  
vendor/extensions (it’s looking for an AppExtension which would be in  
the ‘app’ directory – a standard directory _inside_ individual  
extensions). You should delete the files and try again, with checking  
out the files into vendor/extensions/gallery.

Sean  
p.s. FuzzyBears are dead… Long live FuzzyBears! 😉

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<div class="post-metadata">

**Author:** ![commander](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/df705f/32.png) [@commander](https://www.ruby-forum.com/u/commander)\
**Post date:** [May 12, 2007, 12:45pm UTC](https://www.ruby-forum.com/t/problem-installing-extension/103808/4 "2007-05-12T12:45:19Z")

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Thanks for your detailed answer! Radiant seems to have some problems  
with my Sqlite installation, but using MySQL and following your  
advice, I was able to install the gallery extension.

regards,  
Achim

Am 11.05.2007 um 16:56 schrieb Sean C.: