### Eclipse Workspace Patch 1.0
#P org.eclipse.core.resources
Index: src/org/eclipse/core/internal/resources/LocationValidator.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/LocationValidator.java,v
retrieving revision 1.20
diff -u -r1.20 LocationValidator.java
--- src/org/eclipse/core/internal/resources/LocationValidator.java	8 Oct 2010 16:39:17 -0000	1.20
+++ src/org/eclipse/core/internal/resources/LocationValidator.java	29 Oct 2010 15:21:18 -0000
@@ -12,7 +12,7 @@
 package org.eclipse.core.internal.resources;
 
 import java.net.URI;
-import org.eclipse.core.filesystem.EFS;
+import org.eclipse.core.filesystem.*;
 import org.eclipse.core.filesystem.URIUtil;
 import org.eclipse.core.internal.utils.FileUtil;
 import org.eclipse.core.internal.utils.Messages;
@@ -371,6 +371,17 @@
 				return new ResourceStatus(IResourceStatus.INVALID_VALUE, null, message);
 			}
 		}
+		// test if the given location is read only (bug 285017)
+		try {
+			IFileStore store = EFS.getStore(location);
+			IFileInfo fileInfo = store.fetchInfo();
+			if (FileUtil.fileInfoToAttributes(fileInfo).isReadOnly()) {
+				message = NLS.bind(Messages.resources_readOnly, toString(location));
+				return new ResourceStatus(IResourceStatus.INVALID_VALUE, null, message);
+			}
+		} catch (CoreException e) {
+			return e.getStatus();
+		}
 
 		// Iterate over each known project and ensure that the location does not
 		// conflict with any of their already defined locations.