yes ,but still the user cannot open
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Can't open what? We can't see your screen.
Please share details what you are you are doing because while Windows might support long file names, the application that you are running might not.
Open a Powershell prompt. Copy and paste in these commands.
$LongFolderPath = "$env:TEMP\" + ("A" * 200) + "\" + ("B" * 200) + "\" + ("C" * 200) $LongFolderPath.LengthNew-Item $LongFolderPath -ItemType Directory Remove-Item $LongFolderPathIf that works, then Windows supports long file names. It should look like this. 
If it fails, then run this command.
reg query HKEY_Local_Machine\SYSTEM\CurrentControlSet\Control\FileSystem /v LongPathsEnabledVerify that it is a REG_DWORD and is set to 0x1. 
