As Richard says, the Symbolic Toolbox is effectively MuPad. I've only used it a couple of times, and I can't say that I find it any "friendlier" than the normal Matlab interface when used with its toolbox interface (ie, as an App) ... just different, although I do like the "standard" math notation for the results.
You don't need to type mupad in to use it, though ... or, at least, not in my version ... you can simply use the sym commands, eg:
>> A=hilb(3)
A =
1.0000 0.5000 0.3333
0.5000 0.3333 0.2500
0.3333 0.2500 0.2000
>> sym(A)
ans =
[ 1, 1/2, 1/3]
[ 1/2, 1/3, 1/4]
[ 1/3, 1/4, 1/5]
>> phi=sym('(1+sqrt(5))/2');
>> simplify(phi)
ans =
5^(1/2)/2 + 1/2
>> eval(phi)
ans =
1.6180
>> phi2=(1+sqrt(5))/2
phi2 =
1.6180
>> sym(phi2)
ans =
910872158600853/562949953421312
There are, however, some MuPad features that will only run in the Notebook interface (eg, contfrac).
Overall, I still prefer the look and feel of a Mathcad worksheet, although I think the integration of the symbolic commands could be improved ... I've often wanted to construct a procedure that contains the symbolic commands as an integral 
part of its construction, rather than have them be only available through the separate symbolic evaluation operator; eg, I'd like to write:
f(x):=| sexpr<-asin(x) series,x,10
| fexpr<-sexpr confrac,10
| fexpr
or
f(x):=| sexpr<-series(asin(x). x,10)
| fexpr<-confrac(sexpr,10)
| fexpr
and then symbolically evaluate the function to allow its use by the numerical processor.
Stuart
PS. Mathcad's symbolic processor is a cut-down version of MuPad.
Some history.
Back in the days of MC11 you could add more than one symbolic line to a program. You could only do this by copy and paste though, because it was not officially supported. In fact, it broke the licensing agreement with Maple (which may have had something to do with the switch to MuPad; I'm not sure about that though). So for MC12 and later a program can be evaluated symbolically, but symbolic operations can not be embedded in programs. That rule seems to have stuck, even when the symbolic engine was switched to Mupad. I don't know if that's because of licensing issues, or just because they never changed it. Here's an example in MC11:
Could you explain a bit more in depth how exactly you constructed the file in MC11?
I would if I could remember 
. I created that program a very long time ago, and I don't recall the exact details of how to do it. I do remember that the symbolic expressions can't be typed directly in the program. That restriction was deliberately imposed by Mathsoft, because symbolic expressions within programs violated their licensing agreement with Maple. They accidentally left a loophole though, allowing such programs to be created by copy and paste. You will have to play around a bit to figure out exactly how to do it. I've attached the program, so you can see that it works as advertised 
My OS is win7 (32bits) and I run MC 11 in compatibility mode for XP.
I also run it this way, although I have Win 7 64 bit. It seems to work fine.
