@kestutis Hi,
Thank you for posting in Q&A!
First please understand that Windows 7 support ended on January 14, 2020. Unfortunately, so far I haven't found any solution concerning WES 7 having ARP request issue, the official document is only focusing on WEC 7 having this issue.
Since that we don't have the win7 environment to test, it is suggested you can check the history of Windows 7 Embedded Standard Edition Patches and install the latest update in the Microsoft Update Catalog to test. Thank you for your understanding!
windows+7+embedded+standard+edition+patches
Home.aspx
Hope you have a nice day : )
Gloria
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