Hi all..i just got myself a new ssd and upgraded from win 7 to win 10.
i just finished installing sonar platinum and some of my plug ins and
noticed that they are all listed as "uncategorized" where as in win 7
they were organised  by type  i.e compressor ,reverb etc....
ive tried rescanning but no joy..this is annoying..
any solutions? thanks

You may have to re-categorize the plug-ins if there is no backup of the %appdata%\Cakewalk\Library\Library.db from the old install.
 
VST3 plug-ins automatically get categorized based on the labels in the plug-ins if the manufacturer added any.
 
The rest of the plug-ins do not have this feature and Cakewalk created categories in the database for quite a few but not all non-VST3 plug-ins.
 
Here is the help page about how to maintain plug-in categories.

You'll only have to re-categorize them once. After that, they'll be fine. You can make a backup of library.db to be certain.

thanks but on my win7 drive splat organises  vst 2 plugins perfectly...very annoying

Was %appdata%\Cakewalk\Library\Library.db copied from the Win7 machine to the Win10 machine?

It is not a function of an operating system to categorize audio or MIDI plugins for Sonar.  However, Sonar will give a list based on type if you use VST 3 plugins. You will need to do it yourself for VST 2.4. 
 
Organizing plug-ins
Once you have more than a few plug-in effects and/or soft synths installed on your computer, you might want to
organize the way they appear in the various plug-in and synth menus that you use. The Cakewalk Plug-in
Manager is a powerful tool to organize your plug-in menus. Open the Plug-in Manager by using the Utilities >
Cakewalk Plug-in Manager command, and display the Plug-in Manager’s help file by pressing F1.
By default, plug-ins are sorted by categories such as EQ, Dynamics, Reverb, etc.