If your web client is configured to use an upstream proxy (company proxy), then during recording StresStimulus will chain its proxy with the upstream proxy by reading system proxy settings. While automatic configuration works in most cases, sometimes it fails because of restrictive security policies, interference with other software or if the upstream proxy information cannot be accessed through the system proxy.
In such cases, the upstream proxy configuration should be completed manually. In the main menu go to Options > Gateway Settings to open the StresStimulus Gateway Settings dialog.
Select Manual Proxy Settings and specify a host and port. You can also select use the system proxy settings or use no proxy.
If your test machine is connected to your application via upstream proxy that requires authentication, then during recording, the proxy credentials cached on the test machine will be supplied automatically. Typically the proxy will require your Windows account credentials that are stored on your machine upon you login to your system. Sometimes a different set of credentials is required, but it is likely already stored in the Credential Manager on your machine.
However, if during recording you see login dialog repeatedly appear after entering your credentials, it may be an indication that you need to store the proxy credentials on your machine. To do so in Control Panel on the StresStimulus machine go to Credential Manager. Click Add a Windows credentials and enter your proxy credentials. After that, try recording again.