After I input my credentials, it just stayed on the login page, and did not go to the dashboard. The password is good, we didn't get invalid username and password error.
I opened the trace mode and found this error in the craft.log:
Unable to determine if PATH_INFO is enabled on the server: [curl] 60: Could it cause the error?
The CSRF token could not be verified
2016/12/20 12:52:41 [error] [exception.Craft\HttpException.400] exception 'Craft\HttpException' with message 'The CSRF token could not be verified.' in /var/www/vhosts/xxx.com/master/craft/app/services/HttpRequestService.php:1314 Stack trace:
#0 /var/www/vhosts/xxx.com/master/craft/app/framework/base/CComponent.php(561): Craft\HttpRequestService->validateCsrfToken(Object(CEvent))
#1 /var/www/vhosts/xxx.com/master/craft/app/framework/base/CApplication.php(212): CComponent->raiseEvent('onBeginRequest', Object(CEvent))
#2 /var/www/vhosts/xxx.com/master/craft/app/framework/base/CApplication.php(183): CApplication->onBeginRequest(Object(CEvent))
#3 /var/www/vhosts/xxx.com/master/craft/app/index.php(62): CApplication->run()
#4 /var/www/vhosts/xxx.com/master/public/index.php(20): require_once('/var/www/vhosts...')
#5 {main} REQUEST_URI=/wtuygyq/upuj/duhuhog
#5 {main} REQUEST_URI=/wtuygyq/upuj/duhuhog
- is that request uri real, or did you obfuscate it?