Symtoms:

When you upload the image using the HTTP Put method, you may receive the following error message returned by the ErrorString property:



Cause:

1. The problem may occur if the write permission is not provided on the server.
2. In Tomcat, the value of readonly property is false by default. When the readonly property is set to false, the HTTP Put operation is not allowed.
 
Resolution:

1. Check the write permission at the server.

1). Start Internet Information Services (IIS).
2). Click Web Sites.
3). Right click the specified work folder, select Properties.
4). Select the Write option at the Directory tab.



2. If you are using Tomcat, the doPut() will check to see if the readonly property has been changed to false. If it has not, the HTTP Put operation will be not allowed. Please go to {Tomcat installation directory} -> conf -> web.xml, find the default servlet configuration (org.apache.catalina.servlets.DefaultServlet) and change the readonly property to true.

============================
<init-param>
   <param-name>readonly</param-name>
   <param-value>false</param-value>
</init-param>
============================

References:

HTTPUploadThoughPut