Latitude E5520 with clean install of Windows 10 Pro v1809 onto brand new HDD. Everything works great, except the wireless adapter after a short period of time will show the exclamation mark and it will not communicate with anything. The troubleshoot fails to resolve anything, the drivers are all updated, BIOS included, and Windows updates are current as of this writing. No AV is installed yet, as testing is being done first to prove the laptop is still viable option for the business client. He did not have any wireless problems before, just very slow. Old HDD was in failed state (SMART) and data was recovered only. The data hasn't even been restored yet, until laptop passes all tests in Windows. It has nothing to do with power options, since the laptop doesn't even have to go to screen saver to fail on wireless. The WiFi connection never drops. Disconnecting and reconnecting will solve only temporarily. WLAN is Dell 1501. The laptop doesn't have any verified drivers for Windows 10 (Dell). Appreciate any thoughts.