I've successfully set up O365 calendar sync, and it seems to be working fine. However, we have it configured for 'Only these users', then we nominate the collegues who want to opt in. It's signing in with an O365 admin account.
The problem is, when I click 'Add users', it can't see everyone; older users don't show up (ones created maybe more than three years ago), so I can't add them. Newer users (created within the last three years or so) appear fine.
Does anyone have any suggestions about what might be causing this?
EDIT: having checked again, there are one or two older users showing up - but it seems that all the ones who aren't are older.
The problem is, when I click 'Add users', it can't see everyone; older users don't show up (ones created maybe more than three years ago), so I can't add them. Newer users (created within the last three years or so) appear fine.
Does anyone have any suggestions about what might be causing this?
EDIT: having checked again, there are one or two older users showing up - but it seems that all the ones who aren't are older.
