diff --git a/tests/sshserver.pl b/tests/sshserver.pl
index 4718713e89..c4d0285782 100755
--- a/tests/sshserver.pl
+++ b/tests/sshserver.pl
@@ -588,15 +588,14 @@ push @cfgarr, "# $sshdverstr sshd configuration file for curl testing";
 push @cfgarr, '#';
 
 # AllowUsers and DenyUsers options should use lowercase on Windows
-# and do not support quotes around values for some unknown reason.
+# and do not support quotes around values for an unknown reason.
 if($sshdid =~ /OpenSSH-Windows/) {
     my $username_lc = lc $username;
-    push @cfgarr, "AllowUsers " . $username_lc =~ s/ /\?/gr;
+    push @cfgarr, "AllowUsers " . ($username_lc =~ s/ /\?/gr);  # replace space with '?'
     if(exists $ENV{USERDOMAIN}) {
         my $userdomain_lc = lc $ENV{USERDOMAIN};
         $username_lc = "$userdomain_lc\\$username_lc";
-        $username_lc =~ s/ /\?/g; # replace space with ?
-        push @cfgarr, "AllowUsers " . $username_lc =~ s/ /\?/gr;
+        push @cfgarr, "AllowUsers " . ($username_lc =~ s/ /\?/gr);  # replace space with '?'
     }
 } else {
     push @cfgarr, "AllowUsers $username";