If you have tried to configure the Auto Sign In for Windows Users section of the Extradium Forms-based Authentication Configuration page and you can't get them to work, please follow the steps below to troubleshoot them:
1. In Central Administration --> Monitoring --> Configure diagnostic logging and set “Verbose” for the Trace Level of the Extradium --> WebPart category (as shown in the screenshot below)
2. Use a tool (such as the ULS Deobfuscator tool or the ULS Viewer tool) to monitor the SharePoint ULS log file on the server you will use to test your Auto Sign In settings
3. When you browse the Extradium Sign In page, you should see at least the highlighted line in the ULS log file below (screenshot taken with the ULS Deobfuscator tool). The 2 next lines only appear if Extradium can find an IP Address range that matches the Client IP.
4. If you don't see the first line mentioning the Client IP, it means your IP Address range was probably not added to the proper web application. If you don't see the 2 next lines, make sure your IP Address range includes the Client IP address mentioned on the first line