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php – Symfony profiler throws 404

Posted by: admin April 23, 2020 Leave a comment


I’ve created new project in symfony and I get an error prompt on each site:

An error occurred while loading the web debug toolbar (404: Not Found).
Do you want to open the profiler?

When I open the profiler there is a message

Token not found
Token “59942c” was not found in the database.

Moreover, in the cache directory the profiler directory is empty! I checked permissions and they’re proper. I tried cache:clear and removing cache manually, but that didn’t help.

How to&Answers:

It’s often problem with event subscriber/listener.
Try run

console debug:event

And check for errors


This usually happens if the cache directory is not properly set up to allow the web servers’ user to write data into them.

Under Linux, I would usually use this for development:

php app/console --env=dev cache:clear
php app/console --env=dev cache:warmup
chmod -R a+rwX app/cache/
setfacl -Rm g:www-data:rwX app/cache/
setfacl -Rm g:dev-user:rwX app/cache/

This ensures all required directories will be created and then assigned the required permissions. If you do not have ACL enabled, skip the setfacl commands.

OFC, replace www-data with your web servers’ username, and dev-user with your username.


This is a known bug in the profiler. Since Symfony 2.4, the profiler persisting the data used by the WDT is the very last thing done by Symfony.

The alert you see means that the profiler has not been able to find the token requested in the 2500ms allowed, However if you click OK in the alert, you should be redirected to the profiler and figure out what precisely is slow.


I had the same issue after upgrading Symfony 2.3->2.6. After upgrading web/app_dev.php it fixed the issue. I believe you need the Debug::enable(); line.


Had the same issue after upgrading 2.6 -> 2.8 on a 2.4 era project. Got a useMicrosecondTimestamps error with the node layer. Fixed by nuking rm -r app/cache/*. @marenkay’s method did not clear the node-php server cache.


Try to edit or add your htacces file like this

# Use the front controller as index file. It serves as a fallback solution when
# every other rewrite/redirect fails (e.g. in an aliased environment without
# mod_rewrite). Additionally, this reduces the matching process for the
# start page (path "/") because otherwise Apache will apply the rewriting rules
# to each configured DirectoryIndex file (e.g. index.php, index.html, index.pl).
DirectoryIndex index.php

# By default, Apache does not evaluate symbolic links if you did not enable this
# feature in your server configuration. Uncomment the following line if you
# install assets as symlinks or if you experience problems related to symlinks
# when compiling LESS/Sass/CoffeScript assets.
# Options FollowSymlinks

# Disabling MultiViews prevents unwanted negotiation, e.g. "/index" should not 
# to the front controller "/index.php" but be rewritten to "/index.php/index".
<IfModule mod_negotiation.c>
  Options -MultiViews

<IfModule mod_rewrite.c>
  RewriteEngine On

# Determine the RewriteBase automatically and set it as environment variable.
# If you are using Apache aliases to do mass virtual hosting or installed the
# project in a subdirectory, the base path will be prepended to allow proper
# resolution of the index.php file and to redirect to the correct URI. It will
# work in environments without path prefix as well, providing a safe, one-size
# fits all solution. But as you do not need it in this case, you can comment
# the following 2 lines to eliminate the overhead.
  RewriteCond %{REQUEST_URI}::$1 ^(/.+)/(.*)::$
  RewriteRule ^(.*) - [E=BASE:%1]

# Sets the HTTP_AUTHORIZATION header removed by Apache
  RewriteCond %{HTTP:Authorization} .
  RewriteRule ^ - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

# Redirect to URI without front controller to prevent duplicate content
# (with and without `/index.php`). Only do this redirect on the initial
# rewrite by Apache and not on subsequent cycles. Otherwise we would get an
# endless redirect loop (request -> rewrite to front controller ->
# redirect -> request -> ...).
# So in case you get a "too many redirects" error or you always get redirected
# to the start page because your Apache does not expose the REDIRECT_STATUS
# environment variable, you have 2 choices:
# - disable this feature by commenting the following 2 lines or
# - use Apache >= 2.3.9 and replace all L flags by END flags and remove the
#   following RewriteCond (best solution)
  RewriteCond %{ENV:REDIRECT_STATUS} ^$
  RewriteRule ^index\.php(?:/(.*)|$) %{ENV:BASE}/$1 [R=301,L]

# If the requested filename exists, simply serve it.
# We only want to let Apache serve files and not directories.
  RewriteCond %{REQUEST_FILENAME} -f
  RewriteRule ^ - [L]

# Rewrite all other queries to the front controller.
  RewriteRule ^ %{ENV:BASE}/index.php [L]

<IfModule !mod_rewrite.c>
  <IfModule mod_alias.c>
    # When mod_rewrite is not available, we instruct a temporary redirect of
    # the start page to the front controller explicitly so that the website
    # and the generated links can still be used.
    RedirectMatch 307 ^/$ /index.php/
    # RedirectTemp cannot be used instead