diff --git a/src/dos/dos_ioctl.cpp b/src/dos/dos_ioctl.cpp
index a8cc9fa0..1357bd72 100644
--- a/src/dos/dos_ioctl.cpp
+++ b/src/dos/dos_ioctl.cpp
@@ -152,6 +152,10 @@ bool DOS_IOCTL(void) {
 		return true;
 	case 0x0D:		/* Generic block device request */
 		{
+			if (drive < 2 && !Drives[drive]) {
+				DOS_SetError(DOSERR_ACCESS_DENIED);
+				return false;
+			}
 			if (Drives[drive]->isRemovable()) {
 				DOS_SetError(DOSERR_FUNCTION_NUMBER_INVALID);
 				return false;