Hi GMI Partnership,
To troubleshoot the issue, the following steps are for your reference:
1. Make sure you use Microsoft Office 2007 with Service Pack 2.
2. Run Office desktop setup.
3. Add the URL of your Team Site to the Local Intranet Sites dialog box of your Internet Explorer via http://support.microsoft.com/kb/2807673
For your reference:
Set up your desktop for Office 365
Software requirements for Office 365
If the issue persists, feel free to post the related screenshots here.
Thanks,
Cherry Wang