“This collection cannot be made available to assign policies from Microsoft Endpoint Manager admin center.”
Is that the message you are encountering while trying to make your collection available for MEMAC?
Then read along.
Go to Co-management and double click CoMgmtSettingsProd
Go to the configure upload tab and verify the collection specified. If you are moving slowly forward and not uploading all your devices at once, then this would be the typically configuration.
A reason for not uploading all devices could be due to lack of RBAC implementation. If RBAC has not been configured or thought of, you should start doing that before granted access to the Admin Center (MEMAC)
First collection to be uploaded, should be the one specified in the upload tab on the co-management setup guide.
Limit your collection to the collection you started by uploading.
At last the message:” This collection cannot be made available to assign policies from Microsoft Endpoint Manager admin center” will disappear and you are good to go!
Have some patience. The collection will be populated after some time.