Problems flashing my Lumia 520

[WPCentral Question]

Hi.I tried to flash my Nokia Lumia 520 with the very first firmware version with Product Support Tool for Store 5.0 but i finished with this error:
C:\ProgramData\Nokia\Packages\Products\RM-914\D1AED5FA_RM914_059S3J0_1030.6408.1309.0002_012.vpl has invalid signature.
Exception:
Nokia.Packages.VariantPackage.DataPackage20.VariantPackageSignatureInvalidException: C:\ProgramData\Nokia\Packages\Products\RM-914\D1AED5FA_RM914_059S3J0_1030.6408.1309.0002_012.vpl has invalid signature.
? Nokia.Packages.VariantPackage.DataPackage20.VariantPackageInternal.CheckPackageSignature()
? Nokia.CareSuite.PlugIns.MurzimRecovery.RecoveryDialog.RecoveryDialogModel.<HandleDownloadVariantPackageCompleted>b__b(Object state)

What should i do?Thanks for helping!