Microsoft Power Apps platform access on ProxySG /ASG - apps.powerapps.com

Products

• ASG-S400

Issue/Introduction

Customer's custom web application in Microsoft Powerapps platforom - apps.powerapps.com is not loading correctly via Proxy.

The request was not sent or there was no response from the server. Check your internet connection. Server Response: Table 1 failed: null

When the workstation is on a public network without the proxy, it works fine. Only in the environment with Proxy, the workstation does not load the web application well.

 

Environment

Release : 6.7.5.16

Component :

Cause

You shouldn't send the traffic from endpoint user to Microsoft Power Apps platform consisting (custom apps, Power Bi, Sharepoint etc.) via a proxy. The Power Apps web application isn’t designed to be proxied by any device in the middle of communication – traffic needs to go from endpoint user through firewall then straight to Microsoft service. The direct communication with the Power Apps platform is already secured.

Resolution

Access to Microsoft Power Apps needs to omit any proxy appliance since the web application isn’t designed to be proxied as the developer states in its requirements.

Power Apps does not support running with a proxy enabled. Some proxies (such as Zscaler, Blue Coat) modify Power Apps requests by removing headers (CORS or authentication headers). Power Apps relies on these headers to load the app. Hence, if your app has any problems while loading when proxy is enabled, disable the proxy and then try again.

Source:

• https://docs.microsoft.com/en-us/power-apps/limits-and-config#required-services
• https://docs.microsoft.com/en-us/connectors/common/outbound-ip-addresses 

Note:

Bypass for the Power Apps domains on ProxySG does not provide sufficient workaround. Endpoint user loses some chunks of data needed for web application to load correctly on the web browser (as seen in HAR comparison). It may relate to the CORS or authentication headers from the Power Apps requirements document or different cause that we are not aware. since developer does not provide any additional info how the web application is designed.

If customer needs to use a proxy server:

Some organizations have no option to bypass a proxy for MS Power Apps traffic. If that's the case for you, the problems mentioned above need to be kept in mind.

Customer needs to discuss any possible guidance/workaround for Power Apps with Microsoft Support to run through the customer’s environment with Proxy, since the web application was developed by them and owns the closed code.

Additional Information

Microsoft Support needs to provide guidance for customer if it needs to keep the connection with Proxy based on their environment variables