diff --git a/Cache/BlockCache.cpp b/Cache/BlockCache.cpp
index 24f80d7..f9327fa 100644
--- a/Cache/BlockCache.cpp
+++ b/Cache/BlockCache.cpp
@@ -58,3 +58,18 @@ BlockCache *BlockCache::Create(BlockDevice *device)
     
     return device->createBlockCache();
 }
+
+
+void BlockCache::zeroBlock(unsigned block)
+{
+    /*
+    void *address = acquire(block);
+    std::memset(address, 0, 512);
+    release(block, true);
+    */
+
+    uint8_t buffer[512];
+    
+    std::memset(buffer, 0, 512);
+    write(block, buffer);    
+}
diff --git a/Cache/BlockCache.h b/Cache/BlockCache.h
index 1ee6d40..c4587d1 100644
--- a/Cache/BlockCache.h
+++ b/Cache/BlockCache.h
@@ -36,6 +36,9 @@ public:
     virtual void release(unsigned block, int flags) = 0 ;
     virtual void markDirty(unsigned block) = 0;
     
+    
+    virtual void zeroBlock(unsigned block);
+    
     void release(unsigned block) { release(block, 0); }
     void release(unsigned block, bool dirty) 
     {
diff --git a/Cache/ConcreteBlockCache.cpp b/Cache/ConcreteBlockCache.cpp
index 7fdbba5..a966117 100644
--- a/Cache/ConcreteBlockCache.cpp
+++ b/Cache/ConcreteBlockCache.cpp
@@ -148,6 +148,8 @@ void ConcreteBlockCache::write(unsigned block, const void *bp)
     setLast(e);
 }
 
+
+
 void ConcreteBlockCache::markDirty(unsigned block)
 {
     Entry *e = findEntry(block);
diff --git a/Cache/ConcreteBlockCache.h b/Cache/ConcreteBlockCache.h
index 2560b8e..de46b8b 100644
--- a/Cache/ConcreteBlockCache.h
+++ b/Cache/ConcreteBlockCache.h
@@ -20,6 +20,7 @@ public:
     virtual void release(unsigned block, int flags);
     virtual void markDirty(unsigned block);
 
+    
 
 private:
     struct Entry {
diff --git a/Cache/MappedBlockCache.cpp b/Cache/MappedBlockCache.cpp
index 459e9fa..ba17efe 100644
--- a/Cache/MappedBlockCache.cpp
+++ b/Cache/MappedBlockCache.cpp
@@ -69,6 +69,14 @@ void MappedBlockCache::write(unsigned block, const void *vp)
 }
 
 
+void MappedBlockCache::zeroBlock(unsigned block)
+{
+    _dirty = true;
+    std::memset(_data + block * 512, 0, 512);
+}
+
+
+
 // sync everything.
 void MappedBlockCache::sync()
 {
diff --git a/Cache/MappedBlockCache.h b/Cache/MappedBlockCache.h
index fac9504..951a974 100644
--- a/Cache/MappedBlockCache.h
+++ b/Cache/MappedBlockCache.h
@@ -14,6 +14,8 @@ class MappedBlockCache : public BlockCache {
     virtual void sync();
     virtual void write(unsigned block, const void *vp);
 
+    virtual void zeroBlock(unsigned block);    
+    
 
     virtual void *acquire(unsigned block);
     virtual void release(unsigned block, int flags);
diff --git a/Pascal/File.h b/Pascal/File.h
index 6b7608c..a3c5b7c 100644
--- a/Pascal/File.h
+++ b/Pascal/File.h
@@ -78,6 +78,9 @@ class VolumeEntry : public Entry {
 
 public:
 
+    static unsigned ValidName(const char *);
+
+    
     // create new 
     VolumeEntry(const char *name, Device::BlockDevice *);
     
@@ -103,8 +106,8 @@ public:
     void readBlock(unsigned block, void *);
     void writeBlock(unsigned block, void *);
 
-
-    unsigned static ValidName(const char *);
+    void sync();
+    
     
 protected:
     virtual void writeDirectoryEntry(LittleEndian::IOBuffer *);
diff --git a/Pascal/VolumeEntry.cpp b/Pascal/VolumeEntry.cpp
index 4109212..f76311a 100644
--- a/Pascal/VolumeEntry.cpp
+++ b/Pascal/VolumeEntry.cpp
@@ -77,9 +77,10 @@ VolumeEntry::VolumeEntry(const char *name, Device::BlockDevice *device)
     _cache = BlockCache::Create(device);
     _device = device;
     
+
     for (unsigned i = 2; i < 6; ++i)
     {
-        device->zeroBlock(i);
+        _cache->zeroBlock(i);
     }
     
     void *vp = _cache->acquire(2);
@@ -89,6 +90,7 @@ VolumeEntry::VolumeEntry(const char *name, Device::BlockDevice *device)
         
     _cache->release(2, true);
     
+    _cache->sync();
 }
 
 
@@ -216,6 +218,10 @@ void VolumeEntry::writeBlock(unsigned block, void *buffer)
 }
 
 
+void VolumeEntry::sync()
+{
+    _cache->sync();
+}
 
 void VolumeEntry::writeDirectoryEntry(IOBuffer *b)
 {