If this happens, try this:
1. Download the launch.ica file to a folder on your computer.
2. Right-click the launch.ica and click “open with…”
3. Browse to C:\Program files (x86)\Citrix\Receiver\Receiver.exe
The file will not open, but once ICA files are associated with the Citrix Receiver you should be able to launch applications from your web browser.