diff --git a/Makefile b/Makefile
index 7d5ac61..06598b0 100644
--- a/Makefile
+++ b/Makefile
@@ -51,7 +51,7 @@ TESTS := tests/addr.exe tests/addrcache.exe tests/ethernet.exe tools/fionread.ex
 # Tools to compile before running the test suite.
 TOOLS := tools/socket.exe tools/list-interfaces.exe tools/bind.exe tools/ipx-send.exe \
 	tools/ipx-recv.exe tools/spx-server.exe tools/spx-client.exe  tools/ipx-isr.exe \
-	tools/dptool.exe
+	tools/dptool.exe tools/osversion.exe tools/reg-set-bin.exe
 
 # DLLs to copy to the tools/ directory before running the test suite.
 TOOL_DLLS := tools/ipxwrapper.dll tools/wsock32.dll tools/mswsock.dll tools/dpwsockx.dll
diff --git a/tests/lib/IPXWrapper/Tool/OSVersion.pm b/tests/lib/IPXWrapper/Tool/OSVersion.pm
new file mode 100644
index 0000000..f74bd5b
--- /dev/null
+++ b/tests/lib/IPXWrapper/Tool/OSVersion.pm
@@ -0,0 +1,103 @@
+# IPXWrapper test suite
+# Copyright (C) 2024 Daniel Collins <solemnwarning@solemnwarning.net>
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License version 2 as published by
+# the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program; if not, write to the Free Software Foundation, Inc., 51
+# Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+use strict;
+use warnings;
+
+package IPXWrapper::Tool::OSVersion;
+
+use IPC::Open3;
+use Test::Spec;
+
+my %os_version_cache = ();
+
+sub get
+{
+	my ($class, $host) = @_;
+	
+	if(defined $os_version_cache{$host})
+	{
+		return $os_version_cache{$host};
+	}
+	
+	my @command = ("ssh", $host, "Z:\\tools\\osversion.exe");
+	
+	note(join(" ", @command));
+	
+	# No need for error checking here - open3 throws on failure.
+	my $pid = open3(my $in, my $out, undef, @command);
+	
+	my $output = do {
+		local $/;
+		<$out>;
+	};
+	
+	if($output =~ m/^(\d+).(\d+)\r?\n(\d+)\r?\n(\w+)\r?\n(.*)\r?\n$/)
+	{
+		my $self = bless({
+			major => $1,
+			minor => $2,
+			build => $3,
+			platform => $4,
+			extra => $5,
+		}, $class);
+		
+		$os_version_cache{$host} = $self;
+		
+		return $self;
+	}
+	else{
+		die("Didn't get expected output from osversion.exe:\n$output");
+	}
+}
+
+sub major
+{
+	my ($self) = @_;
+	return $self->{major};
+}
+
+sub minor
+{
+	my ($self) = @_;
+	return $self->{minor};
+}
+
+sub build
+{
+	my ($self) = @_;
+	return $self->{build};
+}
+
+sub platform
+{
+	my ($self) = @_;
+	return $self->{platform};
+}
+
+sub platform_is_win9x
+{
+	my ($self) = @_;
+	return $self->{platform} eq "VER_PLATFORM_WIN32_WINDOWS";
+}
+
+sub platform_is_winnt
+{
+	my ($self) = @_;
+	return $self->{platform} eq "VER_PLATFORM_WIN32_NT";
+}
+
+1;
diff --git a/tests/lib/IPXWrapper/Util.pm b/tests/lib/IPXWrapper/Util.pm
index 6224b8a..a87fc1e 100644
--- a/tests/lib/IPXWrapper/Util.pm
+++ b/tests/lib/IPXWrapper/Util.pm
@@ -1,5 +1,5 @@
 # IPXWrapper test suite
-# Copyright (C) 2014-2017 Daniel Collins <solemnwarning@solemnwarning.net>
+# Copyright (C) 2014-2024 Daniel Collins <solemnwarning@solemnwarning.net>
 #
 # This program is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License version 2 as published by
@@ -55,6 +55,8 @@ use Net::Libdnet::Eth;
 use NetPacket::IPX;
 use NetPacket::IPXWrapper;
 
+use IPXWrapper::Tool::OSVersion;
+
 sub run_remote_cmd
 {
 	my ($host_ip, $exe_name, @exe_args) = @_;
@@ -78,7 +80,21 @@ sub reg_set_dword
 {
 	my ($host_ip, $key, $value, $data) = @_;
 	
-	run_remote_cmd($host_ip, "REG", "ADD", $key, "/v", $value, "/t", "REG_DWORD", "/d", $data, "/f");
+	if(IPXWrapper::Tool::OSVersion->get($host_ip)->platform_is_winnt())
+	{
+		run_remote_cmd($host_ip, "REG", "ADD", $key, "/v", $value, "/t", "REG_DWORD", "/d", $data, "/f");
+	}
+	else{
+		eval { run_remote_cmd($host_ip, "REG", "QUERY", "$key\\$value"); };
+		
+		if($@)
+		{
+			run_remote_cmd($host_ip, "REG", "ADD", "$key\\$value=$data", "REG_DWORD");
+		}
+		else{
+			run_remote_cmd($host_ip, "REG", "UPDATE", "$key\\$value=$data");
+		}
+	}
 }
 
 sub reg_set_addr
@@ -86,33 +102,71 @@ sub reg_set_addr
 	my ($host_ip, $key, $value, $data) = @_;
 	
 	$data =~ s/://g;
-	run_remote_cmd($host_ip, "REG", "ADD", $key, "/v", $value, "/t", "REG_BINARY", "/d", $data, "/f");
+	
+	if(IPXWrapper::Tool::OSVersion->get($host_ip)->platform_is_winnt())
+	{
+		run_remote_cmd($host_ip, "REG", "ADD", $key, "/v", $value, "/t", "REG_BINARY", "/d", $data, "/f");
+	}
+	else{
+		run_remote_cmd($host_ip, "Z:\\tools\\reg-set-bin.exe", $key, $value, $data);
+	}
 }
 
 sub reg_set_string
 {
 	my ($host_ip, $key, $value, $data) = @_;
 	
-	run_remote_cmd($host_ip, "REG", "ADD", $key, "/v", $value, "/t", "REG_SZ", "/d", $data, "/f");
+	if(IPXWrapper::Tool::OSVersion->get($host_ip)->platform_is_winnt())
+	{
+		run_remote_cmd($host_ip, "REG", "ADD", $key, "/v", $value, "/t", "REG_SZ", "/d", $data, "/f");
+	}
+	else{
+		eval { run_remote_cmd($host_ip, "REG", "QUERY", "$key\\$value"); };
+		
+		if($@)
+		{
+			run_remote_cmd($host_ip, "REG", "ADD", "$key\\$value=$data", "REG_SZ");
+		}
+		else{
+			run_remote_cmd($host_ip, "REG", "UPDATE", "$key\\$value=$data");
+		}
+	}
 }
 
 sub reg_delete_key
 {
 	my ($host_ip, $key) = @_;
 	
-	# Attempting to delete a key which doesn't exist is considered to be an
-	# error, so we touch the key beforehand.
+	eval { run_remote_cmd($host_ip, "REG", "QUERY", $key); };
 	
-	run_remote_cmd($host_ip, "REG", "ADD",    $key, "/f");
-	run_remote_cmd($host_ip, "REG", "DELETE", $key, "/f");
+	unless($@)
+	{
+		if(IPXWrapper::Tool::OSVersion->get($host_ip)->platform_is_winnt())
+		{
+			run_remote_cmd($host_ip, "REG", "DELETE", $key, "/f");
+		}
+		else{
+			run_remote_cmd($host_ip, "REG", "DELETE", $key, "/FORCE");
+		}
+	}
 }
 
 sub reg_delete_value
 {
 	my ($host_ip, $key, $value) = @_;
 	
-	run_remote_cmd($host_ip, "REG", "ADD",    $key, "/v", $value, "/t", "REG_SZ", "/f");
-	run_remote_cmd($host_ip, "REG", "DELETE", $key, "/v", $value, "/f");
+	eval { run_remote_cmd($host_ip, "REG", "QUERY", "$key\\$value"); };
+	
+	unless($@)
+	{
+		if(IPXWrapper::Tool::OSVersion->get($host_ip)->platform_is_winnt())
+		{
+			run_remote_cmd($host_ip, "REG", "DELETE", $key, "/v", $value, "/f");
+		}
+		else{
+			run_remote_cmd($host_ip, "REG", "DELETE", "$key\\$value", "/FORCE");
+		}
+	}
 }
 
 sub send_ipx_over_udp
diff --git a/tools/osversion.c b/tools/osversion.c
new file mode 100644
index 0000000..c382073
--- /dev/null
+++ b/tools/osversion.c
@@ -0,0 +1,61 @@
+/* IPXWrapper test tools
+ * Copyright (C) 2024 Daniel Collins <solemnwarning@solemnwarning.net>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#include <windows.h>
+#include <stdio.h>
+
+int main(int argc, char **argv)
+{
+	OSVERSIONINFO osver;
+	osver.dwOSVersionInfoSize = sizeof(osver);
+	
+	if(!GetVersionEx(&osver))
+	{
+		fprintf(stderr, "GetVersionEx: %u\n", (unsigned)(GetLastError()));
+		return 1;
+	}
+	
+	const char *platform;
+	
+	switch(osver.dwPlatformId)
+	{
+		case VER_PLATFORM_WIN32s:
+			platform = "VER_PLATFORM_WIN32s";
+			break;
+			
+		case VER_PLATFORM_WIN32_WINDOWS:
+			platform = "VER_PLATFORM_WIN32_WINDOWS";
+			break;
+			
+		case VER_PLATFORM_WIN32_NT:
+			platform = "VER_PLATFORM_WIN32_NT";
+			break;
+			
+		default:
+			platform = "VER_PLATFORM_UNKNOWN";
+			break;
+	}
+	
+	printf("%u.%u\n%u\n%s\n%s\n",
+		(unsigned)(osver.dwMajorVersion),
+		(unsigned)(osver.dwMinorVersion),
+		(unsigned)(osver.dwBuildNumber),
+		platform,
+		osver.szCSDVersion);
+	
+	return 0;
+}
diff --git a/tools/reg-set-bin.c b/tools/reg-set-bin.c
new file mode 100644
index 0000000..9e6e1f3
--- /dev/null
+++ b/tools/reg-set-bin.c
@@ -0,0 +1,140 @@
+/* IPXWrapper test tools
+ * Copyright (C) 2024 Daniel Collins <solemnwarning@solemnwarning.net>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+/* "Why do you have a standalone program specifically for storing binary
+ * registry values rather than using REG.EXE like you do for everything else?"
+ *
+ * "I'm so glad you asked that, hypothetical voice in my head, BEHOLD."
+ *
+ * > REG ADD HKCU\Software\IPXWrapper\08:00:27:C3:6A:E6\net=00000001 REG_BINARY
+ * > Adding Binary Format Data is not Supported.
+ * > The operation completed successfully.
+*/
+
+#include <windows.h>
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static unsigned char hex_nibble_to_bin(char hex)
+{
+	if(hex >= '0' && hex <= '9')
+	{
+		return 0x0 + (hex - '0');
+	}
+	else if(hex >= 'A' && hex <= 'F')
+	{
+		return 0xA + (hex - 'A');
+	}
+	else if(hex >= 'a' && hex <= 'f')
+	{
+		return 0xA + (hex - 'a');
+	}
+	else{
+		abort();
+	}
+}
+
+int main(int argc, char **argv)
+{
+	if(argc != 4)
+	{
+		fprintf(stderr, "Usage: %s <key path> <value name> <hex string>\n", argv[0]);
+		return 1;
+	}
+	
+	const char *key_path = argv[1];
+	const char *value_name = argv[2];
+	const char *value_hex = argv[3];
+	
+	HKEY root_key;
+	
+	if(strncmp(key_path, "HKLM", 4) == 0 && (key_path[4] == '\\' || key_path[4] == '\0'))
+	{
+		root_key = HKEY_LOCAL_MACHINE;
+		key_path += 4;
+	}
+	else if(strncmp(key_path, "HKCU", 4) == 0 && (key_path[4] == '\\' || key_path[4] == '\0'))
+	{
+		root_key = HKEY_CURRENT_USER;
+		key_path += 4;
+	}
+	else{
+		fprintf(stderr, "Key path must begin with HKLM or HKCU\n");
+		return 1;
+	}
+	
+	if(key_path[0] == '\\')
+	{
+		++key_path;
+	}
+	
+	size_t hex_len = strlen(value_hex);
+	
+	if((hex_len % 2) != 0)
+	{
+		fprintf(stderr, "Invalid byte string\n");
+		return 1;
+	}
+	
+	unsigned char *data = malloc(hex_len / 2);
+	if(hex_len > 0 && data == NULL)
+	{
+		fprintf(stderr, "Error allocating memory\n");
+		return 1;
+	}
+	
+	size_t data_len = hex_len / 2;
+	
+	for(size_t i = 0; i < hex_len; i += 2)
+	{
+		char hex1 = value_hex[i];
+		char hex2 = value_hex[i + 1];
+		
+		if(isxdigit(hex1) && isxdigit(hex2))
+		{
+			data[i / 2] = (hex_nibble_to_bin(hex1) << 4) | hex_nibble_to_bin(hex2);
+		}
+		else{
+			fprintf(stderr, "Invalid byte string\n");
+			return 1;
+		}
+	}
+	
+	HKEY key;
+	DWORD error = RegCreateKeyEx(root_key, key_path, 0, NULL, 0, KEY_READ | KEY_WRITE, NULL, &key, NULL);
+	if(error != ERROR_SUCCESS)
+	{
+		fprintf(stderr, "Error opening/creating registry key (error code %u)\n", (unsigned)(error));
+		return 1;
+	}
+	
+	error = RegSetValueEx(key, value_name, 0, REG_BINARY, (BYTE*)(data), data_len);
+	
+	RegCloseKey(key);
+	free(data);
+	
+	if(error == ERROR_SUCCESS)
+	{
+		return 0;
+	}
+	else{
+		fprintf(stderr, "Error code %u when writing registry value\n", (unsigned)(error));
+		return 1;
+	}
+}