I used Sleep.exe to place a one second delay in the loop to help keep CPU usage down while looping in a failed state.

place on the C: drive in "\bin" folder save in text format with ".bat" as the extension place shortcut to batch file in all users startup test running manually until successful reboot and enjoy ~!

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@echo off
c:
cd\bin
net use y: /d /y

:ch_loop
sleep 1
net use y: \\server\share
if errorlevel 1 goto ch_loop
if not exist y: goto ch_loop

:ch_end
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