Performing a Citrix NetScaler firmware upgrade is generally a pain free process however its not without its pitalls.
If you’ve recently upgraded your NetScaler from one major revision to another for instance and then gone to login to the management GUI you may have come across this little error message that is blocking your progress once you put your credentials in.
Login Command failed over API. Reason; Response not of type text/xml/text/html
Luckily this can be rectified easily, this issue is caused by having a custom Access Gateway logon page which should not be carried over to the newer firmware revisions.
In order to rectify this you’ll need to logon to the NetScaler using Putty or similar and then run the following command.
set vpn parameter -UITHEME DEFAULT
If you are upgrading to a version 11 firmware release the beauty of version 11 is that many of the customisations can be done from the Access Gateway GUI now anyway so all the old css/js file system copying and configuring of old is no longer needed.
Author: Dale Scriven