Server & Data Center
Each user needs to login with their Jira username and password also providing Jira base URL
...
Use your Jira base URL to login (not links to single issue or dashboard etc.)
App do not support any SSO (maybe in the future)
In case of login errors - double check if your login and password are correct, try to access your Jira in browser in incognito mode and use same credentials
In case of any errors, please contact you Jira Administrator first, to help you verify if Excel Connector is configured correctly (e.g. app is added to whitelist Get Started [in Jira] )
If your company’s Jira is running behind firewall etc. you might need to contact responsible team to make sure Jira - Excel communication would be possible
...