diff --git a/tests/DnsClientProbe.Tests.ps1 b/tests/DnsClientProbe.Tests.ps1
index 12b45614..3bb3c4bd 100644
--- a/tests/DnsClientProbe.Tests.ps1
+++ b/tests/DnsClientProbe.Tests.ps1
@@ -8,7 +8,7 @@ Add-Type -Path (Join-Path $ScriptRoot 'scripts/DnsClientProbeNative.cs')
 foreach($resolver in @('127.0.0.1','192.0.2.53','10.0.0.53')){Assert-WelaDnsClientResolver $resolver;Assert ([Wela.DnsClientProbe.Native]::ValidateResolver($resolver) -ceq $resolver) 'Explicit canonical IPv4 accepted.'}
 foreach($resolver in @('','localhost','127.1','127.0.0.01','127.0.0.1:53','127.0.0.1"','0.0.0.0','224.0.0.1','255.255.255.255','192.0.2.999','::1')){Throws {Assert-WelaDnsClientResolver $resolver} 'IPv4';Throws {[Wela.DnsClientProbe.Native]::ValidateResolver($resolver)} 'resolver|IPv4'}
 Throws {[Wela.DnsClientProbe.Native]::Query('arbitrary.example.','127.0.0.1')} 'fixed random'
-foreach($entry in @(@('Request',64),@('QueryResult',32),@('Record',32))){$nativeType=[Wela.DnsClientProbe.Native].GetNestedType($entry[0],[Reflection.BindingFlags]::NonPublic);Assert ([Runtime.InteropServices.Marshal]::SizeOf($nativeType) -eq $entry[1]) ('Native64 SDK layout: '+$entry[0])}
+foreach($entry in @(@('Request',64),@('QueryResult',32),@('Record',32))){$nativeType=[Wela.DnsClientProbe.Native].GetNestedType($entry[0],[Reflection.BindingFlags]::NonPublic);Assert ([Runtime.InteropServices.Marshal].GetMethod('SizeOf',[type[]]@([type])).Invoke($null,@($nativeType)) -eq $entry[1]) ('Native64 SDK layout: '+$entry[0])}
 Assert ([Wela.DnsClientProbe.Native].GetField('SourceSha256').IsLiteral) 'Compiled source fingerprint cannot be reassigned.'
 Assert ([Wela.DnsClientProbe.Native]::Options -eq 2103790) 'Fixed documented DNS flags retained.'
 $fields=@(foreach($name in @('QueryName','QueryType','QueryOptions','QueryStatus','QueryResults')){[pscustomobject]@{Name=$name;InType=$(if($name -in @('QueryName','QueryResults')){'win:UnicodeString'}elseif($name -eq 'QueryOptions'){'win:UInt64'}else{'win:UInt32'})}})