Symptoms

Administrator can't create new project in JIRA

Diagnosis

1. Try create project in different web browser without any Add-Ons
2. Try create project when accesing JIRA directly (eg:  bypassing webserver and network tools like SecureEntryServer(WAF))
3. Try to create project after disabling all User Plugins via Administrations > Manage Add-Ons > Enable Safe Mode and then try to reproduce the ERROR.

4. Ensure the following tomcat attributes are added in the server.xml when integrating Proxy (SSL) with JIRA server:

   scheme="https" proxyName="proxy.atlassian.com" proxyPort="PORT"

   Reference: https://confluence.atlassian.com/kb/cross-site-request-forgery-csrf-protection-changes-in-atlassian-rest-779294918.html

Cause

Some of the JIRA headers are blocked. For example, X-AREQUESTID, X-ASESSIONID, X-AUSERNAME, X-SITEMESH-OFF, X-Atlassian-Token request headers are blocked in the network configuration

Resolution

Ensure that all JIRA's header are not blocked