diff --git a/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfo.java b/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfo.java
index b1e343e5047e624642190212897408d72fc6eb81..2909533baa79fa3c44159731eb1de0df7dceb449 100644
--- a/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfo.java
+++ b/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfo.java
@@ -89,6 +89,8 @@ public interface MetaInfo {
 	 * @return The identity of the initial author.
 	 */
 	public Identity getAuthorIdentity();
+	
+	public boolean hasAuthorIdentity();
 
 	/**
 	 * Corresponds to DublinCore:description
@@ -200,6 +202,9 @@ public interface MetaInfo {
 	
 	public VFSLeaf getThumbnail(int maxWidth, int maxHeight);
 	
+	/**
+	 * Thumbnails are cleared and the metadata file is written on the disk
+	 */
 	public void clearThumbnails();
 
 	/**
diff --git a/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfoFileImpl.java b/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfoFileImpl.java
index a9f4e787b2cac99cc7480dccd2e4d89c80bb4cf1..ec25998cd184262ac053e23d82ef634df5d92559 100644
--- a/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfoFileImpl.java
+++ b/src/main/java/org/olat/core/commons/modules/bc/meta/MetaInfoFileImpl.java
@@ -561,13 +561,18 @@ public class MetaInfoFileImpl extends DefaultHandler implements MetaInfo {
 	 * @see org.olat.core.commons.modules.bc.meta.MetaInfo#getAuthorIdentity()
 	 */
 	public Identity getAuthorIdentity() {
-		if (this.authorIdentKey == null) {
+		if (authorIdentKey == null) {
 			return null;
 		} else {
-			return BaseSecurityManager.getInstance().loadIdentityByKey(this.authorIdentKey);
+			return BaseSecurityManager.getInstance().loadIdentityByKey(authorIdentKey);
 		}
 	}
 
+	@Override
+	public boolean hasAuthorIdentity() {
+		return (authorIdentKey != null);
+	}
+
 	/**
 	 * @see org.olat.core.commons.modules.bc.meta.MetaInfo#getHTMLFormattedAuthor()
 	 */
@@ -808,6 +813,9 @@ public class MetaInfoFileImpl extends DefaultHandler implements MetaInfo {
 		return new LocalFileImpl(thumbnailInfo.getThumbnailFile());
 	}
 	
+	/**
+	 * Thumbnails are cleared and the XML file is written on the disk
+	 */
 	@Override
 	public void clearThumbnails() {
 		cannotGenerateThumbnail = false;
diff --git a/src/main/java/org/olat/core/commons/services/webdav/manager/VFSResourceRoot.java b/src/main/java/org/olat/core/commons/services/webdav/manager/VFSResourceRoot.java
index 2c4cd1294a67adff37b781df2222d80198d72064..0e47b713deacd3f03903cb0aa742fc66afc4aa55 100644
--- a/src/main/java/org/olat/core/commons/services/webdav/manager/VFSResourceRoot.java
+++ b/src/main/java/org/olat/core/commons/services/webdav/manager/VFSResourceRoot.java
@@ -208,7 +208,6 @@ public class VFSResourceRoot implements WebResourceRoot  {
 		}
 		
 		try {
-	        //FileUtils.copy(is, childLeaf.getOutputStream(false));
 	        copyVFS(childLeaf, is);
 		} catch (QuotaExceededException e) {
 			throw e;
@@ -228,10 +227,10 @@ public class VFSResourceRoot implements WebResourceRoot  {
 		
 		if(childLeaf instanceof MetaTagged && identity != null) {
 			MetaInfo infos = ((MetaTagged)childLeaf).getMetaInfo();
-			if(infos != null && infos.getAuthorIdentity() == null) {
+			if(infos != null && !infos.hasAuthorIdentity()) {
 				infos.setAuthor(identity);
 				infos.clearThumbnails();
-				infos.write();
+				//infos.write(); the clearThumbnails call write()
 			}
 		}