-        HeadMethod head = null;
-        try {
-            head = new HeadMethod(client.getWebdavUri() + WebdavUtils.encodePath(mPath));
-            int status = client.executeMethod(head, TIMEOUT, TIMEOUT);
-            client.exhaustResponse(head.getResponseBodyAsStream());
-            boolean success = (status == HttpStatus.SC_OK && !mSuccessIfAbsent) || (status == HttpStatus.SC_NOT_FOUND && mSuccessIfAbsent);
-            result = new RemoteOperationResult(success, status, head.getResponseHeaders());
-            Log.d(TAG, "Existence check for " + client.getWebdavUri() + WebdavUtils.encodePath(mPath) + " targeting for " + (mSuccessIfAbsent ? " absence " : " existence ") + "finished with HTTP status " + status + (!success?"(FAIL)":""));
-            
-        } catch (Exception e) {
-            result = new RemoteOperationResult(e);
-            Log.e(TAG, "Existence check for " + client.getWebdavUri() + WebdavUtils.encodePath(mPath) + " targeting for " + (mSuccessIfAbsent ? " absence " : " existence ") + ": " + result.getLogMessage(), result.getException());
+        AuthenticationMethod authMethod = AuthenticationMethod.UNKNOWN;
+        
+        RemoteOperation operation = new ExistenceCheckRemoteOperation("", mContext, false);
+        client.clearCredentials();
+        client.setFollowRedirects(false);
+        
+        // try to access the root folder, following redirections but not SAML SSO redirections
+        result = operation.execute(client);
+        String redirectedLocation = result.getRedirectedLocation(); 
+        while (redirectedLocation != null && redirectedLocation.length() > 0 && 
+                !result.isIdPRedirection()) {
+            client.setBaseUri(Uri.parse(result.getRedirectedLocation()));
+            result = operation.execute(client);
+            redirectedLocation = result.getRedirectedLocation();
+        } 
+
+        // analyze response  
+        if (result.getCode() == ResultCode.UNAUTHORIZED) {
+            String authRequest = ((result.getAuthenticateHeader()).trim()).toLowerCase();
+            if (authRequest.startsWith("basic")) {
+                authMethod = AuthenticationMethod.BASIC_HTTP_AUTH;
+                
+            } else if (authRequest.startsWith("bearer")) {
+                authMethod = AuthenticationMethod.BEARER_TOKEN;
+            }
+            // else - fall back to UNKNOWN
+                    
+        } else if (result.isSuccess()) {
+            authMethod = AuthenticationMethod.NONE;