diff --git a/core/src/main/java/org/bitcoinj/store/SPVBlockStore.java b/core/src/main/java/org/bitcoinj/store/SPVBlockStore.java
index 53d2325c..de8c0078 100644
--- a/core/src/main/java/org/bitcoinj/store/SPVBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/SPVBlockStore.java
@@ -17,26 +17,19 @@
 package org.bitcoinj.store;
 
 import org.bitcoinj.core.*;
-import org.bitcoinj.utils.Threading;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import org.bitcoinj.utils.*;
+import org.slf4j.*;
 
-import javax.annotation.Nullable;
-import java.io.File;
-import java.io.IOException;
-import java.io.RandomAccessFile;
-import java.nio.ByteBuffer;
-import java.nio.MappedByteBuffer;
-import java.nio.channels.FileChannel;
-import java.nio.channels.FileLock;
-import java.util.Arrays;
-import java.util.LinkedHashMap;
-import java.util.Map;
-import java.util.concurrent.locks.ReentrantLock;
+import javax.annotation.*;
+import java.io.*;
+import java.nio.*;
+import java.nio.channels.*;
+import java.util.*;
+import java.util.concurrent.locks.*;
 
-import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkNotNull;
-import static com.google.common.base.Preconditions.checkState;
+import static com.google.common.base.Preconditions.*;
+
+// TODO: Lose the mmap in this class. There are too many platform bugs that require odd workarounds.
 
 /**
  * An SPVBlockStore holds a limited number of block headers in a memory mapped ring buffer. With such a store, you
@@ -269,9 +262,12 @@ public class SPVBlockStore implements BlockStore {
     public void close() throws BlockStoreException {
         try {
             buffer.force();
+            if (System.getProperty("os.name").toLowerCase().contains("win")) {
+                log.info("Windows mmap hack: Forcing buffer cleaning");
+                WindowsMMapHack.forceRelease(buffer);
+            }
             buffer = null;  // Allow it to be GCd and the underlying file mapping to go away.
             randomAccessFile.close();
-            fileLock.release();
         } catch (IOException e) {
             throw new BlockStoreException(e);
         }
diff --git a/core/src/main/java/org/bitcoinj/store/WindowsMMapHack.java b/core/src/main/java/org/bitcoinj/store/WindowsMMapHack.java
new file mode 100644
index 00000000..d78aee58
--- /dev/null
+++ b/core/src/main/java/org/bitcoinj/store/WindowsMMapHack.java
@@ -0,0 +1,23 @@
+package org.bitcoinj.store;
+
+import sun.misc.*;
+import sun.nio.ch.*;
+
+import java.nio.*;
+
+/**
+ * <p>This class knows how to force an mmap'd ByteBuffer to reliquish its file handles before it becomes garbage collected,
+ * by exploiting implementation details of the HotSpot JVM implementation.</p>
+ *
+ * <p>This is required on Windows because otherwise an attempt to delete a file that is still mmapped will fail. This can
+ * happen when a user requests a "restore from seed" function, which involves deleting and recreating the chain file.
+ * At some point we should stop using mmap in SPVBlockStore and we can then delete this class.</p>
+ *
+ * <p>It is a separate class to avoid hitting unknown imports when running on other JVMs.</p>
+ */
+public class WindowsMMapHack {
+    public static void forceRelease(MappedByteBuffer buffer) {
+        Cleaner cleaner = ((DirectBuffer) buffer).cleaner();
+        if (cleaner != null) cleaner.clean();
+    }
+}