Symfony2: The session id is too long or contains illegal characters

问题

I always get this error when I have some time without updating a project, only occurs in the development environment.

Warning: session_start() [function.session-start]: The session id contains illegal characters, valid characters are a-z, A-Z, 0-9 and '-,'

How to avoid? or Why does this happen?

i use:

• Symfony 2.0.9
• Linux Mint 12 3.0.0-14-generic x86_64
• PHP 5.3.6-13ubuntu3.3

回答1:

You might be using Mink or Behat. Please, make sure that they are loaded only for their environment and not dev/prod. See:

https://github.com/symfony/symfony/issues/1766

回答2:

Delete your browser cookies. It fixed the error for me

来源：https://stackoverflow.com/questions/8811222/symfony2-the-session-id-is-too-long-or-contains-illegal-characters