Hi,
Unfortunately this is a known issue with the eProject 5.0 application. You can notify all users, but it is not possible to notify a subset of more than ~550 users. We have escalated this to our developers, but we currently do not have an estimated resolution time.
In the future, you can feel free to contact Customer Support by using the webform at: http://www.eproject.com/support/enterprise/enterprise_contact.htm .
Thank you,
Kevin Tate
Technical Support Team Lead
eProject, Inc.
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