When you open the web page of the Devolutions Password Server instance, the web page is blank. This is due to a malformed XML web.config file because of a specific parameter that is not supported by IIS version 7 or 7.5. And also a missing json application MIME type in the web application.
These steps are suitable for version 188.8.131.52 and above.
1.Edit the web.config file that is located into the client1.0.0-1 subfolder of the Devolutions Password Server web application folder.
Devolutions Password Server web application folder
2.Remove the setEtag="false" parameter from the web.config file and save the file.
3.Next, open IIS Manager and select the node with your web server name. Then, double-click on the MIME Types icon.
4.In the MIME Type list, if the .json entry doesn't already exist, click on the Add link in the Actions panel on the right and fill in the appropriate field. Set the File name extension field with the value .json and the MIME type field with the value application/json and click on the OK button.
Add .json MIME type
5.No needs to reboot the server or recycle the IIS server after these modifications.