Hi Linson,
Please uninstall the old version and install the new version of Essential Studio 4.4 with the key given to you.
Also could you please check if you have the key for 4.4 got installed in the License Manager?
1) Please get the license manager from,
Start --> All Programs --> Syncfusion --> Essential Studio 4.4.x.x --> Utilities --> License Manager.
2) Please remove the other keys from there, if found any.
We have placed a KnowledgeBase(the kb will be speaking of 4.2.x. It is also the same for 4.4.x), which will deliver some common ideas about the Syncfusion installation and some trouble shooting tips.
http://www.syncfusion.com/support/kb/studio/Default.aspx?ToDo=view&questId=35Also please check that there is no older version of .dll present in both the GAC and in the public assemblies folder.
If you still find the same issue. Please provide us the unlock key and the details displayed in the Syncfusion licensing manager.
Please try this and let me know if this helps.
Thank you for your interest in Syncfusion products.
Regards,
Kumaresh.