Hi there. I didn’t follow the token expired thread(s) in detail, so I don’t know if this has been proposed already: Did you try to delete the cookies from your dolibar installation site?
I.e. in Google Chrome go to your usual dolibarr login page, right click on the lock in the URL bar (or on the circled i if it is not SSL-secured), then click on cookies, then click on the group listed in the window and click on remove (do this for each group, if there is listed more than one).
Disclaimer: I do not have this problem with my website, but it might be that the expired token is stored somewhere in a cookie and removing the cookie will lead to a new, unexpired token. But its based more on a wild guess than on experience.
Besides cleared the browser cache and cookies, I also replicated the installation over a different subdomain and tried on different browser/coockies/incognito window.
Seems that you indeed tried everything possible with regards to cookies/caches. I’m not aware of a particular installation cache.
Probably you researched the forums already. Just in case, there is a thread in the French forum with some proposed changes to make the system work by disabling the security check through commenting three lines:
And there is an even more comprehensive workaround in the German forum:
(Just as a side note for non-French and non-German speakers coming across this - I found the translation feature of Google Chrome quite usable: right click into the foreign website and select the translation from the menu; needs to be disabled for the actual source code snippets, since they get translated, too).