diff --git a/plugins/geenforce/client/ShopdbEnforceClient.psm1 b/plugins/geenforce/client/ShopdbEnforceClient.psm1
index 18492d6..a84d2d5 100644
--- a/plugins/geenforce/client/ShopdbEnforceClient.psm1
+++ b/plugins/geenforce/client/ShopdbEnforceClient.psm1
@@ -58,11 +58,13 @@ function Sync-ShopdbManifest {
             -TimeoutSec 30 -ErrorAction Stop
         if ($response.StatusCode -eq 200) {
             [System.IO.File]::WriteAllText($manifestPath, $response.Content)
-            if ($response.Headers.ETag) {
-                Set-Content -LiteralPath $etagPath -Value $response.Headers.ETag -NoNewline
+            # PowerShell 7 returns header values as string arrays; 5.1 as scalars.
+            # @(...)[0] yields a clean scalar in both.
+            $etag = @($response.Headers['ETag'])[0]
+            if ($etag) {
+                Set-Content -LiteralPath $etagPath -Value $etag -NoNewline
             }
-            $version = $null
-            if ($response.Headers['X-Manifest-Version']) { $version = $response.Headers['X-Manifest-Version'] }
+            $version = @($response.Headers['X-Manifest-Version'])[0]
             if ($version) {
                 Set-Content -LiteralPath (Join-Path $CacheDir "$Scope.version") -Value $version -NoNewline
             }