I have signed up with my personal mail id and activated that, then using the same I hve tried to signin butit throws error like "Sorry, we don't recognize your email address."
Using the RingCentral Phone for Desktop, you can dial or receive test calls, send and receive test SMS or Fax messages in your sandbox environment.
Download RingCentral Phone for Desktop:
Tip: switch to the "sandbox mode" before logging in the app:
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