The U_RN error usually pops up when another license request file is generated after the primary file has been uploaded to the server. 

When the license request file is generated there are number of items that make up the contents of this binary file (it’s really not a text file).  One of the parameters is a time stamp.  When the file is uploaded to the customer portal and the responding UpdateLicense.txt file (another binary file) is generated, the files must have the corresponding time stamp in order for the for the Enterprise Erase application to update the license count.
 
Please follow the instructions below to assist us in resolving this issue: 

1.  Please delete all license request (LicRequest.txt ) and update files (UpdateLicense.txt) from the desktop of the server and USB drives.
2.  Empty your trash bin.
3.  Generate another license request file and keep the file on the desktop.
4.  Upload the new license request file to the customer portal.
5.  Download the UpdateLicense.txt file.
6.  Copy the UpdateLicense.txt file to the desktop.
7.  Update license count.
8.   Once the licenses have been reimbursed to the customer portal account, we will notify you and confirm that you were able to successfully update the license count on the server.