The warning can be disabled using the following steps:

•Go to Tools -> Internet Options -> Security -> Local Intranet

•Click "Custom Level"

•Select "Enable" for "Display mixed content"

•Click "OK"

•Click "OK"

If a call center adapter from another vendor was installed on this computer, uninstall this application and reinstall CTI Data Connector for Salesforce.

The other reason for this error is an installation issue with the Windows XML subsystem, MSXML6, which has not been installed or properly registered. 

•Login as administrator

•Navigate your Windows Explorer to c:\windows\system32

•Double click on msxml6.dll.  It'll give you a window saying it doesn't know what to do with it.  Select "select program from list."

•In the ensuing window, press Browse.  There, type "c:\windows\system32\regsvr32" and confirm the selection with OK

If you get this error, contact salesforce support to enable the API. The API is disabled by default in a test account

If you are using Professional / Enterprise Edition or higher see: API is not enabled for this Organization or Partner

The error message indicates, that the Salesforce Adapter DLL could not be registered

•In case you installed a call center adapter from other vendors uninstall it and delete the adapter within salesforce

•Quit CTI Data Connector for Salesforce (blue icon, right mouse click, Quit)

•Install CTI Data Connector for Salesforce again using Windows Administrator credentials

•If the error persists send us a log file

If you are using a test account see: Error connecting to the salesforce.com AppExchange API - the SoftPhone does not load

If you are using Professional / Enterprise Edition or higher, check the profile (Setup, Administration Setup, Manage Users, Profiles) which is associated to the user.  There is an option: API Enabled. This must be checked. Also verify if the option: Call Center is checked with the option Visible

DLLs have not been registered properly. Install CTI Data Connector for Salesforce again using Windows Administrator credentials
 
Note for Administrators: The file SF_MSApi4.dll is not registered. It is in the folder c:\program files\CTI Data Connector for salesforce 4.0\call center adapter and can be manually registered using regsvr32

This error means that the XML subsystem, MSXML6, has not been installed or properly registered. Search "Unable to start the Softphone XML subsystem." in Salesforce.com Help & Training for troubleshooting steps.
 

•Download MSXML6 Parser .Restart Windows after installation

 
Note for Administrators: The file msxml6.dll is missing or not registered. It is in the folder c:\windows\system32 and can be manually registered using regsvr32

Error Message

.

The error message indicates, that different versions of the Salesforce Adapter DLL are installed

•In case you installed a call center adapter from other vendors uninstall it and delete the adapter within salesforce

•Quit CTI Data Connector for Salesforce (blue icon, right mouse click, Quit)

•Install CTI Data Connector for Salesforce again using Windows Administrator credentials

•If the error persists send us a log file

See Browser Support

Right to the phone number there is a grey icon  instead of a green icon or the text: click to dial disabled is displayed when you click  on a phone number

Check if the red salesforce icon is visible  See also System Tray icon.

The icon is NOT visible

The icon is visible