09-21-2016 01:16 PM
Most likely related to the different version of Java that is installed.
For the switch you would like to manage with webtools do the following:
run firmwareshow command and note the firmware on the switch
Go to my.brocade.com and select Downloads from the gray bar on top. Then go to Product Downloads, FOS, and find your firmware version in the list. Click on the firmware level (example 7.4.1) and expand the drop-down. Locate the Release Notes and click on that to download the pdf of the Rel Notes. Search in the document for "Java", and you will be taken to the specific Java release and version for use on that switch. Install the correct Java version on the management server you are using to access the webtools client on the switch.
Also note that due to all the security leaks in Java, the security settings within the applet have been changed and may need to be adjusted. I don't know how to change the security settings, but you'll get the idea from a google search on that.