Hi, Kelsoz - I know we can sound like a bunch of MIDI elitist snobs in our replies, but that's because we can get so weary from hearing newcomers bring up the same questions that have been answered a million times. When you said, "...I'm really trying to get X1 to recognize the "built in" midi output drivers that other programs recognize..." us boring, Sonar pros immediately know that you don't know what's good for you. In a phrase--you don't Want X1 to recognize and use that last century piece of crap (as Daveny so delicately described it). If you want MIDI files to sound decent, start using real soft synths. That's all there really is to it--and please pardon the no paragraph breaks. This Forum software is so lame that when you're using Firefox, you can't do any formatting. RB

I am having the same problem, but by following the instructions above (thanks Juca for the kind and patiently delivered advice) I did get GS Wavetable to reappear and then it woks. I am happy to try and get other possibly better solutions to work (I.E. Soft Synths) but when I try to use them I am back to getting silence and also it appears in my menus that GS Wavetable is the only midi output device I can use and that will only be available if I run MME.
 
And please guys, all I am seeking here is help. I do not need sarcastic comments about my newness nor editorials about old vs new software. If I was an expert I would probably not be here in the forums seeking help. If I am asking a question for the thousandth time I apologize but as a newbie I am not going to be able to know about the other 999 time. Please all remember that they set this forum up so that the experienced members could help the newbies, not just berate them for being new.

In a phrase--you don't Want X1 to recognize and use that last century piece of crap (as Daveny so delicately described it)

Its not like I was telling him he had to go buy something else. I just said use the better of the ones that come with the product. Sorry if "crap" was offensive. 

STAY AWAY FROM THE WAVETABLE SYNTH! I spent almost a month trying to figure out why my drivers would not change in other programs like Notion 3. I kept getting the alert that another device was using the driver and that program neede to be shut down in order to release the drivers. I finally found out after weeks of trouble shooting that the GS Wavetable somehow had been selected and it would not release the driver for other synths and programs to operate. I unchecked the GS and everything went back to normal. A huge waste of time! Believe me, it is worth the extra time and effort to setup a template with TTS-1 in it. Use import to load the the midi file. The GS Wavetable IS a piece of crap! Again, No offense intended!

BTW, I was running in ASIO mode when I had all these problems with the GS. I don't mean to sound like I'm on a rant, but, when I have had so much trouble with a feature on a product that I have almost 15 years of experience with I feel moved to be pretty strong about not potentially causing yourself more problems. Especially if you are a newbie. Also, if you are a newbie, it seems to me you would rather take the extra time to figure out how MIDI and soft synths work as opposed to just turning on the GS. The GS is not a very good sounding board for the potential of the the MIDI. I have on occasion almost not used a song because it sounded so cheesy on the GS, only to find that it really sounded good thru the soft synths included in Sonar. Bottom line, the more experience you have using the plugin synths in Sonar the better.

"If you read the op, you know I have a fine audio interface etc. I would feel lost without having the MS GS as with that I can quickly audition and edit multi-track MIDI files one after another - zip zip zip. Here, sound quality is of diminished interest, composition and structure are of great interest. Using TTS-1 in this mode would not be so quick. The real next choice for me is to run the midi into the Fantom X GM banks." This! Got a new PC setup and can't find GS Wavetable in any driver mode. The computer will play MIDI files just fine. Any ideas?

Where of course it is excellent advice to recommend using a "better" midi playback device, I think what the OP is trying to do is legit.

 There is no point writing MIDI tracks using the TTs-1 that will be ultimately be played back on the billions of MS wavetable synths the average pc person will be using to listen with. 
Do not forget that there are many MIDI composers out there who enjoy posting songs as pure MIDI. Very few people will load these songs into a DAW. 
It may sound like cheese, but it is the "standard" 
And don't forget you old timers! We used to pay #1,000- $2,000 for a sound module that sounded worse.   

It is a huge PITA to load MIDI files into Sonar just to audition them. 

Yeah, I don't load them in just to audition them. I just wanted to avoid more replies of "X sounds better". I like to work with GS for certain things. Any idea at all why I can't find it under any driver?