diff --git a/cdm/core/src/main/java/ucar/nc2/internal/ncml/AggregationExisting.java b/cdm/core/src/main/java/ucar/nc2/internal/ncml/AggregationExisting.java
index d81fc325d7..fa528c229d 100644
--- a/cdm/core/src/main/java/ucar/nc2/internal/ncml/AggregationExisting.java
+++ b/cdm/core/src/main/java/ucar/nc2/internal/ncml/AggregationExisting.java
@@ -321,7 +321,7 @@ protected void persistRead() {
 
     Element aggElem;
     try {
-      aggElem = ucar.nc2.util.xml.Parse.readRootElement("file:" + cacheFile.getPath());
+      aggElem = ucar.nc2.util.xml.Parse.readRootElement(cacheFile.toURI().toString());
     } catch (IOException e) {
       if (debugCache) {
         System.out.println(" No cache for " + cacheName + " - " + e.getMessage());