--- upnphttp.c.orig	2014-08-26 23:09:22.000000000 +0200
+++ upnphttp.c	2015-03-07 19:27:16.000000000 +0100
@@ -1903,10 +1903,38 @@
 		}
 	}
 
+	/* Perform several checks to pin down the file access problem */
+
+	/*sleep (15); */
+
+	DPRINTF(E_ERROR, L_HTTP, "Starting debug on file %s ----------------\n", last_file.path);
+	
+	DPRINTF(E_ERROR, L_HTTP, "Real UID of the process %i\n", getuid());
+	DPRINTF(E_ERROR, L_HTTP, "Real GID of the process %i\n", getgid());
+	DPRINTF(E_ERROR, L_HTTP, "Effective UID of the process %i\n", geteuid());
+	DPRINTF(E_ERROR, L_HTTP, "Effective GID of the process %i\n", getegid());
+
+	struct stat file_attr;
+	int stat_res;
+	stat_res = stat(last_file.path,&file_attr);
+
+	DPRINTF(E_ERROR, L_HTTP, "Mode of file %hu\n", file_attr.st_mode );
+	DPRINTF(E_ERROR, L_HTTP, "UID of file %u\n", file_attr.st_uid );
+	DPRINTF(E_ERROR, L_HTTP, "GID of file %u\n", file_attr.st_gid );
+	
+	int access_r,access_w,access_x;
+	access_r = access( last_file.path, R_OK );
+	access_w = access( last_file.path, W_OK );
+	access_x = access( last_file.path, X_OK );
+	if( access_r == -1 ) {DPRINTF(E_ERROR, L_HTTP, "Error opening for READ %s [%s]\n", last_file.path, strerror( errno ));}
+	if( access_w == -1 ) {DPRINTF(E_ERROR, L_HTTP, "Error opening for WRITE %s [%s]\n", last_file.path, strerror( errno ));}
+	if( access_x == -1 ) {DPRINTF(E_ERROR, L_HTTP, "Error opening for EXEC %s [%s]\n", last_file.path, strerror( errno ));}
+
+
 	offset = h->req_RangeStart;
 	sendfh = open(last_file.path, O_RDONLY);
 	if( sendfh < 0 ) {
-		DPRINTF(E_ERROR, L_HTTP, "Error opening %s\n", last_file.path);
+		DPRINTF(E_ERROR, L_HTTP, "Error opening %s [%s]\n", last_file.path, strerror( errno ));
 		Send404(h);
 		goto error;
 	}