MSFN is made available via donations, subscriptions and advertising revenue. The use of ad-blocking software hurts the site. Please disable ad-blocking software or set an exception for MSFN. Alternatively, register and become a site sponsor/subscriber and ads will be disabled automatically.
Try this Intel driver: https://downloadcenter.intel.com/download/24555/Intel-Ethernet-Drivers-for-Microsoft-Embedded-Operating-Systems It says "for XP Embedded" but it (obviously) works just fine on regular XP. Extract from the readme file (DriverSelectionGuide.txt): Good luck!
The problem lies in the fact that from September the 1st, HKLM\SOFTWARE\Microsoft\Microsoft Antimalware\EndOfLifeState key changed from 0x2 (Grace period. OS has reached end-of-life, but anti-malware platform service is still running and definition updates can be received) to 0x3 (Anti-malware service stopped. You can no longer start the anti-malware service). As suspected by heinoganda, replacing the gui (msseces.exe) is no longer sufficient. @heinoganda Any chance to try your last modded MSE?
You can find an archived copy of the hexalter tool here: http://web.archive.org/web/20150430211221/http://kuwanger.net/misc/hexalter.shtmlA big thank you, heinoganda, for the fast and easy solution. No need to say that it works perfectly. Regards.