Hi,
I've transfer a number of X3 projects to a new computer with Sonar Platinum and it cannot find a number of synths and plugins that and installed on the new computer.   I made sure all the dll's are in the right folders, when I load these projects the screen comes up that it is unable to find these synths and plugins.  I've made sure the proper folders are being searched in the Plugin Manager.   Is it possible to see where the program is looking for these synths and plugins from the FX box in the Track view or the  Browser or anywhere else.   They are there in the right folders, but the computer is still night finding them.   Specifically,  Addictive Drums 1 and Breverb 2.   I have Addictive Drums 2 installed, but these projects were done with AD1.   
 
Thanx

Do a reset and rescan of your VST from the Plugin Manager this might help.

Are they located in a different location than they were on your old machine.  
i.e. 
C:\Program Files\VSTPlugIns
rather than 
C:\Program Files\Cakewalk\Vstplugins

Was the old machine 32 bit and the new machine 64 bit?

How did the AD1 dll get on the machine? Was it installed with the XLN installer?

Hi, I rescanned a number of times.  They are in the same folders and they were both 64bit computers.

Did you reset the plug-ins in addition to re-scanning?

Hi,
I want to retain the settings I set from my mix.
If I reset to plugins, I'll lose all my settings

you have 4 different threads, basically all the same issue.
I believe once you solve your missing plug in problem you will solve all 4.
which probably would have been better to put them all in the same thread,
that being said, filling out your sig with system details, audio interface, exc might also help.
(if not help in the future as well).
 
1- you have to open Cakewalk command center and make sure to download all the new platinum downloads.
(suites - synths - VSTs - VST I's ,exc)
 
2-verify the plug ins are in the correct folder.
 
3-open the plug in manager and make sure the PIM is scanning those folders with said plug ins.
 
4-rescan / reset if still not finding them.(check the box=rescan failed plug ins)
 
I know you said you want to retain your plug in settings but what is worse..not having those settings or not having those plug ins ?
though im not even sure what you mean by that. are you saying that resetting the plug in manager flush your presets or something ?
 

A reset and rescan of your plugins does not loose any of the settings in the plugs themselves it just clears and rebuilds the list of installed plugs.