java.lang.IllegalArgumentException: Invalid token ''

refer below thread-

https://forums.adobe.com/thread/2335853

Tried restarting using bin/start but did not work for me ...cleared cookies nd tried logging in but still did not help...

Could u pls have a look at this thread as well-

How to close user session after 30 minutes of inactivity In AEM 6.1

Specifically this one-

• Also make sure to set Token Length otherwise will throw exception "org.eclipse.jetty.servlet.ServletHandler / java.lang.IllegalArgumentException: Invalid token ''"

I am not able to open any of the consoles now , it is only throwing that exception on every console, is there anything else I should do to have a successful login

Try deleting launchpad folder-

crx-quickstart\launchpad

and restart the server.

It is taking so long to load and start after deletion of launchpad folder..will it take some time or something is wrong ..

It will take time keep monitoring the bundles under launchpad folder..

Instance startup stopped I believe I can see few folders came up in launchpad folder ..it is at the same point as 2 hours back not starting

Please check the logs.

If you are seeing segment not found then follow steps given in below link to fix that issue-

Fix Inconsistencies in the repository when SegmentNotFound Issue is reported in AEM 6.x

Hope you were able to resolve this..