Support

Let's make sure that the problem is indeed caused by Admin Tools. In order to do so, try the following:

1. Try setting the Error Reporting level in your Global Configuration to "None". Many errors are caused by harmless PHP Notices and Warnings being output to the browser, breaking anything which requires HTTP header manipulation such as Joomla!'s session management, AJAX calls and download systems.

2. Try to replicate the issue after disabling the "System - Admin Tools" plugin. If you can still replicate the issue, it is not caused by Admin Tools. Disabling that plugin means that Admin Tools code (including the Web Application Firewall) is not running on your site.

3. If you suspect an issue with the .htaccess file, replace its contents with the contents of the stock htaccess.txt file shipped with every version of Joomla!. If you are on GoDaddy please wait for 1-30 minutes for the changes to be effective. Then, retry loading the problem page. If you can still reproduce the error, then it is not caused by .htaccess Maker.

If doing any of the above resulted in the issue still occurring, it's not related with Admin Tools and I can't help you. If doing any of the above did stop the issue from occurring, we'll have to do some troubleshooting.

First go to Admin Tools, Web Application Firewall, Configure WAF. Make sure "Log security exceptions" is set to Yes; if it's not, set it to Yes and click on Save. Now try reproducing your issue. Immediately after that, please go to Admin Tools, Web Application Firewall, Security Exceptions Log and go to the last page. The last log entry should have the date and time of when the issue occurred. Please copy the Reason and Target URL here so that I can help you.

If, however, you do not see a log entry, or the Date and/or IP address do not match your last access, this problem is not caused by Admin Tools' WAF. In this case, you will have to do some .htaccess troubleshooting. You may need to read the general .htaccess troubleshooting page, as well as the page on finding out necessary .htaccess exceptions.

I will try to explain this to you, despite the fact that it should be self understood. Here is what you said, in your very own words:

The problem still persist after uninstalling Admin Tools.

When you uninstall a component from a site, its code is removed from your server. If the code is not on your server, it doesn't run. If the code which is no longer on the server does not run it can not affect your site. It's software, not witchcraft.

The only thing that could be left behind and I did mention in my instructions is the .htaccess file, if AND ONLY IF you used the .htaccess Maker feature of Admin Tools. Since you said this:

I tried all the above steps from 1-3

you have already tried getting rid of Admin Tools' .htaccess file. Therefore, there is no leftover from Admin Tools which could be affecting your site.

Regarding The "Fix Permissions", if it did cause a problem you would have no access to your site. If you don't believe me, you can ask your host to reset the ownership and permissions on your site. In fact, please do so that you understand once and for all that Admin Tools IS NOT related to your issue.

For what is worth, what you're describing is a session management issue. Usually turning off cache works wonders. If you're using a browser with fetch-ahead (like Firefox and Chrome) that may also contribute to the Invalid Token issue. But I'm not going to offer support for a generic Joomla! problem just because, contrary to any shred of common sense, you insist that it's a problem caused by Admin Tools which you have already UNINSTALLED from your site.