For people to place Skype or Lync calls from within Microsoft Dynamics CRM, the phone numbers must be entered and stored in a valid number format: <country/region code><area code><number>. However, when entering data in Microsoft Dynamics CRM, users may not include the required country or region prefix in a phone number.
To solve this, you can enable country/region code prefixing, and the system will prefix the code to the number that you are trying to call. This prefixing can be done for the entire organization, or users can set the country or region code in their personal options. If a user has specified a different code than what is set for the organization, the user's setting overrides the organization's setting.
Make sure you have the System Administrator security role or equivalent permissions in Microsoft Dynamics CRM.
Check your security role
Follow the steps for the app you're using.
If using the CRM web application
On the nav bar, click or tap Microsoft Dynamics CRM > Settings.
Settings appears on the nav bar.
Click or tap Settings > Administration > System Settings.
If using CRM for Outlook
In the Navigation Pane, expand your organization if necessary, and then click or tap Settings > System > Administration, and then click or tap System Settings.
On the General tab, in the Set the default country/region code section, select the Enable country/region code prefixing check box, and then in the Country/Region Code Prefix, specify the country/region code, such as +01181 (81 is the country code for Japan).
Click or tap OK.