SSRS Report fails to load in iframe – can’t connect

I was experiencing an issue with connecting to an SSRS report when some report request form data was changed. Larger reports would fail, leading me to believe there was a timeout associated with this. I adjusted the ReceiveTimeout entry in the following reg key:

HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings

to 60000 (decimal).

This resolved the issue for me.