diff --git a/source/virtual/vcart.c b/source/virtual/vcart.c
index fcde5f7..6753e6e 100644
--- a/source/virtual/vcart.c
+++ b/source/virtual/vcart.c
@@ -22,6 +22,7 @@ bool ReadVCartDir(VirtualFile* vfile, VirtualDir* vdir) {
     GetCartName(name, cdata);
     memset(vfile, 0, sizeof(VirtualFile));
     vfile->keyslot = 0xFF; // unused
+    vfile->flags = VFLAG_READONLY;
         
     while (++vdir->index <= 5) {
         if ((vdir->index == 0) && (cdata->data_size < FAT_LIMIT)) { // standard full rom
@@ -45,7 +46,7 @@ bool ReadVCartDir(VirtualFile* vfile, VirtualDir* vdir) {
         } else if ((vdir->index == 5) && (cdata->cart_type & CART_CTR)) { // private header
             snprintf(vfile->name, 32, "%s-priv.bin", name);
             vfile->size = PRIV_HDR_SIZE;
-            vfile->flags = VFLAG_PRIV_HDR;
+            vfile->flags |= VFLAG_PRIV_HDR;
             return true;
         }
     }
diff --git a/source/virtual/vgame.c b/source/virtual/vgame.c
index d41b2da..7e8b622 100644
--- a/source/virtual/vgame.c
+++ b/source/virtual/vgame.c
@@ -726,7 +726,7 @@ bool OpenVGameDir(VirtualDir* vdir, VirtualFile* ventry) {
 bool ReadVGameDirLv3(VirtualFile* vfile, VirtualDir* vdir) {
     vfile->name[0] = '\0';
     BuildLv3Index(&lv3idx, romfslv3);
-    vfile->flags = VFLAG_LV3;
+    vfile->flags = VFLAG_LV3 | VFLAG_READONLY;
     vfile->keyslot = ((offset_ncch != (u64) -1) && NCCH_ENCRYPTED(ncch)) ? 
         0x2C : 0xFF; // actual keyslot may be different
     
@@ -801,7 +801,7 @@ bool ReadVGameDirNitro(VirtualFile* vfile, VirtualDir* vdir) {
     u8* fat = nitrofs + twl->fat_offset - twl->fnt_offset;
         
     vfile->name[0] = '\0';
-    vfile->flags = VFLAG_NITRO;
+    vfile->flags = VFLAG_NITRO | VFLAG_READONLY;
     vfile->keyslot = 0;
     
     // start from parent dir object
@@ -863,8 +863,9 @@ bool ReadVGameDir(VirtualFile* vfile, VirtualDir* vdir) {
     }
     
     if (++vdir->index < n) {
-        // copy current template to vfile
+        // copy current template to vfile and set readonly flag
         memcpy(vfile, templates + vdir->index, sizeof(VirtualFile));
+        vfile->flags |= VFLAG_READONLY;
         return true;
     }
     
diff --git a/source/virtual/virtual.c b/source/virtual/virtual.c
index 19656aa..7932790 100644
--- a/source/virtual/virtual.c
+++ b/source/virtual/virtual.c
@@ -170,7 +170,9 @@ int WriteVirtualFile(const VirtualFile* vfile, const void* buffer, u64 offset, u
         count = vfile->size - offset;
     if (bytes_written) *bytes_written = count;
     
-    if (vfile->flags & (VRT_SYSNAND|VRT_EMUNAND|VRT_IMGNAND)) {
+    if (vfile->flags & VFLAG_READONLY) {
+        return -1;
+    } else if (vfile->flags & (VRT_SYSNAND|VRT_EMUNAND|VRT_IMGNAND)) {
         return WriteVNandFile(vfile, buffer, offset, count);
     } else if (vfile->flags & VRT_MEMORY) {
         return WriteVMemFile(vfile, buffer, offset, count);
diff --git a/source/virtual/virtual.h b/source/virtual/virtual.h
index d6232df..da5d950 100644
--- a/source/virtual/virtual.h
+++ b/source/virtual/virtual.h
@@ -7,26 +7,27 @@
 #define VRT_EMUNAND NAND_EMUNAND
 #define VRT_IMGNAND NAND_IMGNAND
 #define VRT_XORPAD  NAND_ZERONAND
-#define VRT_MEMORY  (1UL<<10)
-#define VRT_GAME    (1UL<<11)
-#define VRT_TICKDB  (1UL<<12)
-#define VRT_KEYDB   (1UL<<13)
-#define VRT_CART    (1UL<<14)
+#define VRT_MEMORY  (1UL<<4)
+#define VRT_GAME    (1UL<<5)
+#define VRT_TICKDB  (1UL<<6)
+#define VRT_KEYDB   (1UL<<7)
+#define VRT_CART    (1UL<<8)
 
 #define VRT_SOURCE  (VRT_SYSNAND|VRT_EMUNAND|VRT_IMGNAND|VRT_XORPAD|VRT_MEMORY|VRT_GAME|VRT_TICKDB|VRT_KEYDB|VRT_CART)
 
-#define VFLAG_DIR       (1UL<<16)
-#define VFLAG_ROOT      (1UL<<17)
-#define VFLAG_LV3       (1UL<<18)
+#define VFLAG_DIR       (1UL<<10)
+#define VFLAG_ROOT      (1UL<<11)
+#define VFLAG_READONLY  (1UL<<12)
+#define VFLAG_LV3       (1UL<<13)
 
 
 #define VRT_DRIVES  {'S', VRT_SYSNAND}, {'E', VRT_EMUNAND}, {'I', VRT_IMGNAND}, {'X', VRT_XORPAD }, \
                     {'M', VRT_MEMORY}, {'G', VRT_GAME}, {'K', VRT_KEYDB}, {'T', VRT_TICKDB}, {'C', VRT_CART}
 
 // virtual file flag (subject to change):
-// bits 0...9  : reserved for NAND virtual sources and info
-// bits 10...15: reserved for other virtual sources
-// bits 16...18: reserved for external flags
+// bits 0...3  : reserved for NAND virtual sources and info
+// bits 4...9  : reserved for other virtual sources
+// bits 10...18: reserved for external flags
 // bits 19...31: reserved for internal flags (different per source, see vgame.c)
 typedef struct {
     char name[32];
diff --git a/source/virtual/vkeydb.c b/source/virtual/vkeydb.c
index 56b41ed..1ed8cbe 100644
--- a/source/virtual/vkeydb.c
+++ b/source/virtual/vkeydb.c
@@ -50,6 +50,7 @@ bool ReadVKeyDbDir(VirtualFile* vfile, VirtualDir* vdir) {
         vfile->offset = vdir->index * sizeof(AesKeyInfo);
         vfile->size = 16; // standard size of a key
         vfile->keyslot = 0xFF;
+        vfile->flags = VFLAG_READONLY;
         
         return true; // found
     }
diff --git a/source/virtual/vtickdb.c b/source/virtual/vtickdb.c
index d7c5171..e967bd3 100644
--- a/source/virtual/vtickdb.c
+++ b/source/virtual/vtickdb.c
@@ -113,7 +113,7 @@ bool ReadVTickDbDir(VirtualFile* vfile, VirtualDir* vdir) {
             vfile->offset = tick_entry->offset;
             vfile->size = sizeof(Ticket);
             vfile->keyslot = 0xFF;
-            vfile->flags = vdir->flags & ~VFLAG_DIR;
+            vfile->flags = (vdir->flags | VFLAG_READONLY) & ~VFLAG_DIR;
             
             return true; // found
         }
@@ -123,6 +123,7 @@ bool ReadVTickDbDir(VirtualFile* vfile, VirtualDir* vdir) {
         while (++vdir->index < n_templates) {
             // copy current template to vfile
             memcpy(vfile, templates + vdir->index, sizeof(VirtualFile));
+            vfile->flags |= VFLAG_READONLY;
             return true; // found
         }
     }