[megaloman]

Код:

@Echo Off
	Call :DelSuff "Z:\Box_In\F-LDR*__My.*" "__My"
	Call :AddSuff  "Z:\Box_In\F-LDR*.*" "__My"
Exit /B

:DelSuff
	FOR /F "usebackq delims=" %%d IN (`2^>nul Dir %1 /S /B /A:D ^|Sort /R`) DO (
		Set "N=%%~nd" &Call Ren "%%d" "%%N:__My=%%%%~xd"
	)
Exit /B

:AddSuff
	FOR /F "usebackq delims=" %%d IN (`2^>nul Dir %1 /S /B /A:D ^|Sort /R`) DO (
		Call Ren "%%d" "%%~nd%~2%%~xd"
	)
Exit /B