diff --git a/src/d_netfil.c b/src/d_netfil.c
index a6b37186a..ffd39eef9 100644
--- a/src/d_netfil.c
+++ b/src/d_netfil.c
@@ -116,7 +116,7 @@ UINT8 *PutFileNeeded(void)
 	for (i = 0; i < numwadfiles; i++)
 	{
 		// If it has only music/sound lumps, don't put it in the list
-		if (W_VerifyNMUSlumps(wadfiles[i]->filename))
+		if (!wadfiles[i]->important)
 			continue;
 		else
 			filestatus = 1; // Importance - not really used any more, holds 1 by default for backwards compat with MS
@@ -339,7 +339,7 @@ INT32 CL_CheckFiles(void)
 		CONS_Debug(DBG_NETPLAY, "game is modified; only doing basic checks\n");
 		for (i = 1, j = 1; i < fileneedednum || j < numwadfiles;)
 		{
-			if (j < numwadfiles && W_VerifyNMUSlumps(wadfiles[j]->filename))
+			if (j < numwadfiles && !wadfiles[j]->important)
 			{
 				// Unimportant on our side.
 				++j;
diff --git a/src/w_wad.c b/src/w_wad.c
index 32c2f3e6c..cf8e7aab0 100644
--- a/src/w_wad.c
+++ b/src/w_wad.c
@@ -298,6 +298,7 @@ UINT16 W_LoadWadFile(const char *filename)
 	INT32 compressed = 0;
 	size_t packetsize;
 	UINT8 md5sum[16];
+	boolean important;
 
 	if (!(refreshdirmenu & REFRESHDIR_ADDFILE))
 		refreshdirmenu = REFRESHDIR_NORMAL|REFRESHDIR_ADDFILE; // clean out cons_alerts that happened earlier
@@ -320,7 +321,7 @@ UINT16 W_LoadWadFile(const char *filename)
 	// Check if wad files will overflow fileneededbuffer. Only the filename part
 	// is send in the packet; cf.
 	// see PutFileNeeded in d_netfil.c
-	if (!W_VerifyNMUSlumps(filename))
+	if ((important = !W_VerifyNMUSlumps(filename)))
 	{
 		packetsize = packetsizetally;
 
@@ -474,6 +475,7 @@ UINT16 W_LoadWadFile(const char *filename)
 	wadfile->handle = handle;
 	wadfile->numlumps = (UINT16)numlumps;
 	wadfile->lumpinfo = lumpinfo;
+	wadfile->important = important;
 	fseek(handle, 0, SEEK_END);
 	wadfile->filesize = (unsigned)ftell(handle);
 
diff --git a/src/w_wad.h b/src/w_wad.h
index f7ea64a56..a9ca29b35 100644
--- a/src/w_wad.h
+++ b/src/w_wad.h
@@ -70,6 +70,7 @@ typedef struct wadfile_s
 	FILE *handle;
 	UINT32 filesize; // for network
 	UINT8 md5sum[16];
+	boolean important; // also network - !W_VerifyNMUSlumps
 } wadfile_t;
 
 #define WADFILENUM(lumpnum) (UINT16)((lumpnum)>>16) // wad flumpnum>>16) // wad file number in upper word