@Juli I have moved this post to the Integrations forum as it was originally posted to the Unified CRM extension group, which is a different product. First, I am sorry for the difficulty you are having. It sounds frustrating, so let me see if I can help. But one disclaimer - I am not an expert in our Salesforce integration. 

The information you have provided may not be sufficient for us to completely diagnose the problem you are having. First, the dialer should obviously work if you are logged into RingCentral properly, and into the correct account. That should go without saying, but I want to be thorough. Next, have you checked your calling preferences? It is possible you have phone preferences that could be interfering. But there may also be a Salesforce setting that is also interfering.

Or of course neither of these things. 

So another thing to do is take a quick step back and check a few things:

• Can you confirm that you can receive calls from the RingCentral Desktop App?
• Can you confirm that you can place calls from the Salesforce integration?

I want to confirm that you can make and receive calls from somewhere. Then we can narrow the problem down within Salesforce?