A forbidden HTTP communication or protocol was used.

Your account does not have permission to sync with your current settings. Contact your Microsoft Exchange administrator.

Case 1: “This server uses an SSL connection” was unchecked.

Case 2: Make sure Microsoft-Server-ActiveSync is not setup to " DENIED ACCESS”. To check it:
1. Open IIS.
2. Expand Web Sites -> Default Web Site.
3. Open the Properties page of Microsoft-Server-ActiveSync.
4. In Directory Security tab, click Edit under “IP address and domain name restrictions”.
5. Make sure that you configured as Granted access.

Case 3: Make sure Exchange/Exchange-oma virtual directories are setup correctly.
1. Open IIS Manager
2. Open properties of virtual directory Exchange/Exchange-oma
3. Select Directory Security tab
4. Select Edit in Authentication and access control box. Make sure the authentication setting as below:
Authentication Methods
Enabled Basic authentication
Enabled Integrated Windows authentication
Disabled anonymous access

Case 4: make sure OMA virtual directory and Microsoft-Server-ActiveSync virtual directories are setup correctly'
1. Open IIS Manager
2. Open properties of OMA virtual directory and Microsoft-Server-ActiveSync virtual directory respectively.
3. Select Directory Security tab
4. Select Edit in Authentication and access control box. Make sure the
authentication setting as below:
Authentication Methods
Uncheck Enable anonymous access
Uncheck Integrated Windows authentication
Check Basic authentication

Related Topics

ActiveSync Troubleshooting
ActiveSync Support Codes, Errors, Resolution and Cases