Invalid Returned Data from License Server
This is a network/firewall issue and needs to be resolved on your end.
If you have recently installed any new software this could be the culprit especially if the software has a built-in Firewall.
See the document below for some suggestions on how to resolve this issue. In addition, pay attention to what is loading up at login time. You might want to try disabling one program at a time to see if a program starting up at login is causing the problem.
<a target=_blank href="http://www.fluentusers.com/support/installation/winfaq/invalid_ret_dat.htm">http://www.fluentusers.com/support/installation/winfaq/invalid_ret_dat.htm</a>http://www.fluentusers.com/support/installation/winfaq/invalid_ret_dat.htm
If after reading the suggestions in the posted document and you are still getting this error when trying to access the license server send the following information to email@example.com.
Click on the Start Menu, Programs, Accessories, System Tools.
Choose System Information.
Click on the File Menu, Save As System Information File.
As well as the FLUENT application and version you are trying to use.
<a target=_blank href="http://www.fluentusers.com/support/installation/winfaq/index.htm">http://www.fluentusers.com/support/installation/winfaq/index.htm</a>http://www.fluentusers.com/support/installation/winfaq/index.htm