User/computer delegation error when importing certificates

I'm doing a plain and simple certificate import, but I'm getting an error I haven't seen before:

Exception calling "Import" with "3" argument(s): "The requested operation cannot be completed. The computer must be trusted for delegation and the current user account must be configured to allow delegation."

Anyone know what could cause this?

$cred = Get-Credential remoteuser

$certs = (Get-Content -Raw C:\certs\cert01.pfx),(Get-Content -Raw C:\certs\cert02.pfx),(Get-Content -Raw C:\certs\cert03.pfx)

Invoke-Command -ComputerName dmz01,dmz02 -Credential $cred -ScriptBlock {

    if(-not (Test-Path D:\software\certs)) { mkdir D:\software\certs\ }

    $using:certs[0] | Set-Content D:\software\certs\cert01.pfx
    $using:certs[1] | Set-Content D:\software\certs\cert02.pfx
    $using:certs[2] | Set-Content D:\software\certs\cert03.pfx

    $store = Get-Item cert:\LocalMachine\TrustedPeople
    $store.Open('ReadWrite')

    'cert01.pfx','cert02.pfx','cert03.pfx' | % {

        try {
            $cert = New-Object System.Security.Cryptography.X509Certificates.X509Certificate2
            $cert.Import("D:\software\certs\$_", 'password', 'DefaultKeySet')
            $store.Add($cert)
        }
        catch {
            Write-Warning "$_"
        }

    }

    $store.Close()
}