Hello JW_FEI,
Thank you for your information, we did find 500 HTTP error, and recommend you check how many admin roles have assigned to your account. You can let admin removing additional admin roles
in admin center and check the result again : About admin roles
For if one account has too many roles, the size of JWT token is bigger than 4K.
OWA reuses JWT token data to set OpenId Connect authentication cookie. Because of the JWT size, the overall cookie length exceeds 4K, and some browsers, e.g. Chrome and Safari, don't set the cookie at all. The old Edge and Internet Explorer allow setting
cookie value longer as 4k.
You may need to make sure that your account doesn't belong to many of
AAD roles as well. These roles are not EXO groups but AAD roles. You could let admin help checking roles membership at AAD Admin Portal or using
Azure AD PowerShell.
$rolegroups=Get-MsolRole | select ObjectID
$rolegroups | %{Get-MsolRoleMember -RoleObjectId $_.ObjectID | ? {$_.EmailAddress -eq "******@domain.com"}}
The output will just repeat the address of the account as many times as it is a member in an Azure AD Role group, you will not see the actual role groups in which the account is a member.
Kind Regards,
Anna