# In \`const\_missing': uninitialized constant CGI::Session **URL:** \ **Category:** Rails\ **Created:** [June 21, 2010, 9:41am UTC](https://www.ruby-forum.com/t/in-const-missing-uninitialized-constant-cgi-session/190475 "2010-06-21T09:41:25Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![gandhi-tush](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/5daacb/32.png) [@gandhi-tush](https://www.ruby-forum.com/u/gandhi-tush)\ **Post date:** [June 21, 2010, 9:41am UTC](https://www.ruby-forum.com/t/in-const-missing-uninitialized-constant-cgi-session/190475/1 "2010-06-21T09:41:25Z")
Hi, I have an application which previously running on rails 2.2.2. I just upgraded the rails to 2.3.8. After that I tried to start the server I got the following error:- “/usr/local/ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.8/lib/active\_support/dependencies.rb:105:in `const\_missing’: uninitialized constant CGI::Session (NameError” Anyone have any idea How to solve this issue? I already renamed my application.rb to application\_controller.rb Thanks, Tushar ---
**Author:** ![gandhi-tush](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/5daacb/32.png) [@gandhi-tush](https://www.ruby-forum.com/u/gandhi-tush)\ **Post date:** [June 21, 2010, 11:18am UTC](https://www.ruby-forum.com/t/in-const-missing-uninitialized-constant-cgi-session/190475/2 "2010-06-21T11:18:26Z")
On Jun 21, 8:41 am, Tushar G. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Hi, > I have an application which previously running on rails 2.2.2. I just > upgraded the rails to 2.3.8. After that I tried to start the server I > got the following error:- > “/usr/local/ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.8/lib/active\_supp ort/dependencies.rb:105:in > `const\_missing’: uninitialized constant CGI::Session (NameError” Session handling was rejigged in 2.3. Search for anywhere you’re using CGI::Session and see what the internet has to say about accomplishing what you were attempting to do Fred