where can i get on board stlink binary file used by B-L475E-IOT01 board ?

[Jpark.1]

I erased on board stlink firmware by mistake.

I got STLinkV2.J16.S4 bin file from a web site . and downloaded it into on board stlink with STM32 ST-LINK Utility.

and then upgraded STLinkV2.J34.S4 to on board stlink by using ST-LinkUpgrade tool

but L475E board doesn't work properly..

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