Publishing error signtool reported an error "failed to sign bin/debug/ltcy_client.publish // setup.exe.

///// Error 2 signtool reported an error "failed to sign bin/debug/ltcy_client.publish // setup.exe. Signtool error: isignedcode: Sign returned error: 0x80880253

//// The signers certificate is not valid for signing.

///// Signtool error: An error occurred while attempting to sign: Bin/debug/ltcy_client.publish // setup.exe

//////". Ltcy_client Error 1: A project cannot be generated, so it cannot be released. 1 1 ltcy_client

 

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Open Project Properties
Select Signature Tab
Click "create test certificate"
Set Password (can be blank)