I have the same issue.
It's not my cache
It's not my browser
It's not my OS
It's not my router
I've tried it all. It suddenly stopped working for me last October. I have literally tried 12 computers and three different networks. Two OS's, and 4 different browsers. All have the same issue. One of the PC's was a brand new computer, literally used for the first time. I turned off firewalls as well. I even tried my phone once. Not a single successful attempt.
On TurboTax the Cobrowse button link at the bottom tells me about a code, but there is no actual code displayed.
I suspect the issue is with my account. Intuit is the only company I am unable to screen share or allow remote access with. I also lost the ability to view reports on Quickbooks Time which is why I had to cancel the service. No support rep was able to figure out what the issue was, they always blamed my setup, and never attempted to look into my suggestion that something is wrong with my intuit account that is preventing this.
I am going to make a new account to prove this out, wish I thought of this weeks ago.
