1- MAke sure that you are usin Microsoft IE , not other applications.
2-MAke sure that you upgrade the java to the last version .
3-MAke sure that you clean the microsoft IE cash & history .
4-add the U1960 ip address to the trusted zone .
5-check the U1960 SW version and upload the web file pakage to the U1960 using the TFTP .
Config download file wbfile
while upgrade may be the web file is damaged while upgrading .
while upgrade don't add the web file to the all file list . just upload it along.