Hi @Anonymous ,
Has it always been like this, or have you had any changes recently?
Any other errors/warning events in the Operations Manager event log?
You could go through the links mentioned in the similar old forum post over here:
https://social.technet.microsoft.com/Forums/en-US/a8535f7f-83f0-4c77-858e-ea80a1d9e163/scom-reports-issue-unable-to-open-the-reports-in-scom-console-not-loading-at-all-blank-screen?forum=operationsmanagerreporting
PS: Since this also involves SCOM, you could add the msc-operations-manager-reporting tag to your question.
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Best regards,
Leon