diff --git a/src/d_clisrv.c b/src/d_clisrv.c
index 939d53de..76b5c95d 100644
--- a/src/d_clisrv.c
+++ b/src/d_clisrv.c
@@ -1733,9 +1733,7 @@ static boolean CL_ServerConnectionSearchTicker(boolean viams, tic_t *asksent)
 {
 #ifndef NONET
 	INT32 i;
-#endif
 
-#ifndef NONET
 	// serverlist is updated by GetPacket function
 	if (serverlistcount > 0)
 	{
@@ -1769,7 +1767,20 @@ static boolean CL_ServerConnectionSearchTicker(boolean viams, tic_t *asksent)
 				serverlist[i].info.fileneeded);
 			CONS_Printf(M_GetText("Checking files...\n"));
 			i = CL_CheckFiles();
-			if (i == 2) // cannot join for some reason
+			if (i == 3) // too many files
+			{
+				D_QuitNetGame();
+				CL_Reset();
+				D_StartTitle();
+				M_StartMessage(M_GetText(
+					"You have too many WAD files loaded\n"
+					"to add ones the server is using.\n"
+					"Please restart SRB2 before connecting.\n\n"
+					"Press ESC\n"
+				), NULL, MM_NOTHING);
+				return false;
+			}
+			else if (i == 2) // cannot join for some reason
 			{
 				D_QuitNetGame();
 				CL_Reset();
diff --git a/src/d_netcmd.c b/src/d_netcmd.c
index 478772ed..d7bbb0aa 100644
--- a/src/d_netcmd.c
+++ b/src/d_netcmd.c
@@ -3078,7 +3078,13 @@ static void Got_RequestAddfilecmd(UINT8 **cp, INT32 playernum)
 	filestatus_t ncs = FS_NOTFOUND;
 	UINT8 md5sum[16];
 	boolean kick = false;
+	boolean toomany = false;
 	INT32 i;
+	size_t packetsize = 0;
+	serverinfo_pak *dummycheck = NULL;
+
+	// Shut the compiler up.
+	(void)dummycheck;
 
 	READSTRINGN(*cp, filename, 240);
 	READMEM(*cp, md5sum, 16);
@@ -3104,13 +3110,25 @@ static void Got_RequestAddfilecmd(UINT8 **cp, INT32 playernum)
 		return;
 	}
 
-	ncs = findfile(filename,md5sum,true);
+	// See W_LoadWadFile in w_wad.c
+	for (i = 0; i < numwadfiles; i++)
+		packetsize += nameonlylength(wadfiles[i]->filename) + 22;
 
-	if (ncs != FS_FOUND)
+	packetsize += nameonlylength(filename) + 22;
+
+	if ((numwadfiles >= MAX_WADFILES)
+	|| (packetsize > sizeof(dummycheck->fileneeded)))
+		toomany = true;
+	else
+		ncs = findfile(filename,md5sum,true);
+
+	if (ncs != FS_FOUND || toomany)
 	{
 		char message[256];
 
-		if (ncs == FS_NOTFOUND)
+		if (toomany)
+			sprintf(message, M_GetText("Too many files loaded to add %s\n"), filename);
+		else if (ncs == FS_NOTFOUND)
 			sprintf(message, M_GetText("The server doesn't have %s\n"), filename);
 		else if (ncs == FS_MD5SUMBAD)
 			sprintf(message, M_GetText("Checksum mismatch on %s\n"), filename);
@@ -3180,10 +3198,15 @@ static void Got_Addfilecmd(UINT8 **cp, INT32 playernum)
 
 	ncs = findfile(filename,md5sum,true);
 
-	if (ncs != FS_FOUND)
+	if (ncs != FS_FOUND || !P_AddWadFile(filename, NULL))
 	{
 		Command_ExitGame_f();
-		if (ncs == FS_NOTFOUND)
+		if (ncs == FS_FOUND)
+		{
+			CONS_Printf(M_GetText("The server tried to add %s,\nbut you have too many files added.\nRestart the game to clear loaded files\nand play on this server."), filename);
+			M_StartMessage(va("The server added a file \n(%s)\nbut you have too many files added.\nRestart the game to clear loaded files.\n\nPress ESC\n",filename), NULL, MM_NOTHING);
+		}
+		else if (ncs == FS_NOTFOUND)
 		{
 			CONS_Printf(M_GetText("The server tried to add %s,\nbut you don't have this file.\nYou need to find it in order\nto play on this server."), filename);
 			M_StartMessage(va("The server added a file \n(%s)\nthat you do not have.\n\nPress ESC\n",filename), NULL, MM_NOTHING);
@@ -3201,7 +3224,6 @@ static void Got_Addfilecmd(UINT8 **cp, INT32 playernum)
 		return;
 	}
 
-	P_AddWadFile(filename, NULL);
 	G_SetGameModified(true);
 }
 
diff --git a/src/d_netfil.c b/src/d_netfil.c
index bf4e5987..70e9ce56 100644
--- a/src/d_netfil.c
+++ b/src/d_netfil.c
@@ -330,6 +330,12 @@ INT32 CL_CheckFiles(void)
 	INT32 i, j;
 	char wadfilename[MAX_WADPATH];
 	INT32 ret = 1;
+	size_t packetsize = 0;
+	size_t filestoget = 0;
+	serverinfo_pak *dummycheck = NULL;
+
+	// Shut the compiler up.
+	(void)dummycheck;
 
 //	if (M_CheckParm("-nofiles"))
 //		return 1;
@@ -378,6 +384,10 @@ INT32 CL_CheckFiles(void)
 		return 1;
 	}
 
+	// See W_LoadWadFile in w_wad.c
+	for (i = 0; i < numwadfiles; i++)
+		packetsize += nameonlylength(wadfiles[i]->filename) + 22;
+
 	for (i = 1; i < fileneedednum; i++)
 	{
 		CONS_Debug(DBG_NETPLAY, "searching for '%s' ", fileneeded[i].filename);
@@ -397,6 +407,14 @@ INT32 CL_CheckFiles(void)
 		if (fileneeded[i].status != FS_NOTFOUND || !fileneeded[i].important)
 			continue;
 
+		packetsize += nameonlylength(fileneeded[i].filename) + 22;
+
+		if ((numwadfiles+filestoget >= MAX_WADFILES)
+		|| (packetsize > sizeof(dummycheck->fileneeded)))
+			return 3;
+
+		filestoget++;
+
 		fileneeded[i].status = findfile(fileneeded[i].filename, fileneeded[i].md5sum, true);
 		CONS_Debug(DBG_NETPLAY, "found %d\n", fileneeded[i].status);
 		if (fileneeded[i].status != FS_FOUND)