I have had X1 for  a couple of years now. (since just before they announced X2) 
  But now I am formalizing what I do an I am currently studying  sound engineering. There my problems begin.
  Sidechaining in logic (Belezebub) Is a really easy affair It is a nice DAW though I still prefer Sonar because of its ease of use in general.  But I need to be able to sidechain and that is proving difficult so far. I have read all the bumf online watched a few vids but nothing works. I have VSTs that I know are capable of sidechaining but how ever I try i can not make the send see the gate or compressor.
So my question is.... Is it even possible in essential and if so how can i do this?
 
Steve
AMD FX4100 3.6ghz 6gb 1.6ghz ddr3 ram E-Mu 0404 sound card Asus mainboard windows 7 X64

Whoa! I don't know what was included in X1 Essential. I do know that Studio and Producer will support sidechaining.  
 
 
 

Compressor mode. For details, see “ProChannel (Producer and Studio only)” on page 999.

I should mention that the above post is from Sonar X3. 

X1 Essentials did not include the full Sonitus Suite, only the EQ and Reverb. A similar thread was asked a few years ago http://forum.cakewalk.com/FindPost/2314771. Which plug-ins are failing?

Yeah. I have seen that before. It's not much different from Sonar 8. It does seem to indicate that it is possible in essential. As it says:
"In addition, ProChannel (Producer only) supports sidechaining when using the PC4K S-Type Bus
Compressor mode. For details, see “ProChannel (Producer and Studio only)” on page 999."
If it isn't possible I must admit I would be disappointed again. Same as when I had to buy the MP3 encoder. 
It's all the extras you have to buy. I will have to think about either upgrading or getting a DAW with that ability thats more mainstream in a studio.
 
 

Ok. Thanks. but I am still none the wiser. I have tried exactly that.  No plugin shows as available even though I know they have that ability. Unless its some kind of rewire?

What sidechainable plug-ins have you tried that don't work in X1 Essential? It sure seems (based on the post referenced by scook) that it supports sidechaining.
 
As to "extras," Cakewalk offers different levels of programs at different price points, and entry-level versions like Essentials have fewer extras. For example, there were some people on this forum who had already tricked out X2 with Melodyne and Addictive Drums, and had all the plug-ins they needed...so they upgraded to X3 Studio instead of Producer and saved some money. 
 
IIRC the reason the MP3 encoder costs extra is because of licensing. There are so many ways to convert files to MP3 format these days for free, it's understandable that most users would not want to have part of their purchase price go for something they don't want or need.

I wouldn't have minded if it was included in the price (IE. it cost the extra  in the first place) but thats beside the point. I have blue tubes that the VST says in the settings that it has the inputs
 

There were some updates in X1a WRT sidechain. Hopefully the installation is patched at least to X1a although X1d would be better.

steverobbins
Ok. Thanks. but I am still none the wiser. I have tried exactly that.  No plugin shows as available even though I know they have that ability. Unless its some kind of rewire?

Please understand a few things. First I can't tell you anything about Sonar Essential because I know nothing about it. Also its an old product.  At present the equivalent is Sonar X3 and few of us have it. What most users have is either the Studio or Producer package. I do know as a matter of fact that Sonar Producer supports sidechaining because I have implemented it in a project. I can't say this about the entry level product. I suspect it does though.
 
It is very dependent on the plugin used. Not all plugins support it and cannot be sidechained. There are more now than in the post that do. You need to list which plugin you are using to sidechain. It could be it wont allow it. Or it could be user error. 
 
Notice I say plugin not VST or DX because both are fully support by Sonar.