diff --git a/dlls/mountmgr.sys/device.c b/dlls/mountmgr.sys/device.c
index ccb0685cedd..6db088f11ee 100644
--- a/dlls/mountmgr.sys/device.c
+++ b/dlls/mountmgr.sys/device.c
@@ -26,6 +26,7 @@
 #include <stdarg.h>
 #include <stdio.h>
 #include <fcntl.h>
+#include <unistd.h>
 #include <sys/time.h>
 #ifdef HAVE_SYS_IOCTL_H
 # include <sys/ioctl.h>
@@ -1026,6 +1027,14 @@ static BOOL get_volume_device_info( struct volume *volume )
     if (!unix_device)
         return FALSE;
 
+#ifdef __APPLE__
+    if (access( unix_device, R_OK ))
+    {
+        WARN("Unable to open %s, not accessible\n", debugstr_a(unix_device));
+        return FALSE;
+    }
+#endif
+
     if (!(name = wine_get_dos_file_name( unix_device )))
     {
         ERR("Failed to convert %s to NT, err %u\n", debugstr_a(unix_device), GetLastError());
diff --git a/dlls/mountmgr.sys/diskarb.c b/dlls/mountmgr.sys/diskarb.c
index 12da89d7688..25e0745372a 100644
--- a/dlls/mountmgr.sys/diskarb.c
+++ b/dlls/mountmgr.sys/diskarb.c
@@ -25,6 +25,7 @@
 #include <errno.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <unistd.h>
 #ifdef HAVE_SYS_IOCTL_H
 # include <sys/ioctl.h>
 #endif
@@ -150,7 +151,8 @@ static void appeared_callback( DADiskRef disk, void *context )
     else
         if (guid_ptr) add_volume( device, device, mount_point, DEVICE_HARDDISK_VOL, guid_ptr, NULL );
 
-    if ((fd = open( device, O_RDONLY )) >= 0)
+    if (!access( device, R_OK ) &&
+        (fd = open( device, O_RDONLY )) >= 0)
     {
         dk_scsi_identify_t dsi;