Below are some useful resources and some answers to common issues with reaching or starting the websites.

Useful logs

IIS Requests Logs

If you need to investigate your network configuration to see the content of HTTP requests, you can find IIS log files :

1. Open IIS Manager (run inetmgr)
2. Click on the Sites list to get the ID of the desired website. For example in this screenshot, the Alpana3App ID is 2 :

IIS website ID

3. With Windows file explorer, browse the following folder (replace the 2 with your desired ID from step 2. above) :


4. This folder contains logs as space-separated text files ordered by date, containing all requests.

Browser errors

Sometimes, the web browser console gives indications on the nature of the problem.

See your web browser documentation to open the console.
For Google Chrome, press F12 and click the “Console” tab.

Problem : Frontend website loading forever

You are trying to open the Frontend website, but you have a white page with a loading animation that never completes :

Server frontend loading

Possible explanation : Wrong Frontend address used


Check the web browser console for an error like :

Access to XMLHttpRequest at '' from origin 'http://yy.yy.yy.yy' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

Check that you can reach the Backend from your same web browser on the same URL, and see a login page there.


If so, a possible explanation is :
Your Backend at is configured to not respond to queries from http://yy.yy.yy.yy.

For example, when you install Alpana Server and configure to use a domain name with as Frontend and as Backend, you won’t be able to access the Frontend using its IP address yy.yy.yy.yy.
That’s for security reasons : the Frontend will only be allowed to talk to the Backend if it calls from the pre-defined origin (the domain name
That is configured through CORS rule internally.


You can solve this case by redirecting requests in IIS.
For example, if you wish to be able to reach the Frontend from IP address yy.yy.yy.yy, you need to let IIS listen to requests to http://yy.yy.yy.yy and redirect them to the accepted domain name

See IIS documentation examples on how to do this.

Last modified: Sep 13, 2021


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