I have same problem after migrating from windows 10 with corporate openVPN config to windows 11 workplace. Scripts in this thread did not help me. And i made my own. May be this help someone else... Just replace registry path in Get-ItemPropertyValue with yours stored path and run this script in power shell window... Worked in Windows 10x64, OpenVPN 2.4.9

$keyBinEncrupted = Get-ItemPropertyValue 'HKCU:\SOFTWARE\OpenVPN-GUI\configs\corpnet' 'key-data'
$entropyBin = Get-ItemPropertyValue 'HKCU:\SOFTWARE\OpenVPN-GUI\configs\corpnet' 'entropy'
$entropyBin = $entropyBin[0..(($entropyBin.Length)-2)]

$keyBinDecrupted = [System.Security.Cryptography.ProtectedData]::Unprotect(
    $keyBinEncrupted,
    $entropyBin,
    [System.Security.Cryptography.DataProtectionScope]::CurrentUser)

Write-Host ([System.Text.Encoding]::Unicode.GetString($keyBinDecrupted))

I have same problem after migrating from windows 10 with corporate openVPN config to windows 11 workplace. Scripts in this thread did not help me. And i made my own. May be this help someone else... Just replace registry path in Get-ItemPropertyValue with yours stored path and run this script in power shell window... Working in Windows 10x64, OpenVPN 2.4.9

$keyBinEncrupted = Get-ItemPropertyValue 'HKCU:\SOFTWARE\OpenVPN-GUI\configs\corpnet' 'key-data'
$entropyBin = Get-ItemPropertyValue 'HKCU:\SOFTWARE\OpenVPN-GUI\configs\corpnet' 'entropy'
$entropyBin = $entropyBin[0..(($entropyBin.Length)-2)]

$keyBinDecrupted = [System.Security.Cryptography.ProtectedData]::Unprotect(
    $keyBinEncrupted,
    $entropyBin,
    [System.Security.Cryptography.DataProtectionScope]::CurrentUser)

Write-Host ([System.Text.Encoding]::Unicode.GetString($keyBinDecrupted))