Why solve function doesn´t work in Matlab 2013b but there isn't any problem with Matlab 2010b?

Hello:

I am using the solve function (Symbolic Toolbox) for solving non-linear equation systems corresponding to material balances in Chemical Engineering. The attached file is solved without problems with Matlab 2010b version:

physical_solution =

[ F1, 100.0] [ F10, 1156.25] [ F11, 106.25] [ F12, 200.0] [ F2, 105.0] [ F3, 390.0] [ F4, 2500.0] [ F5, 2475.0] [ F6, 2381.25] [ F7, 476.25] [ F8, 1905.0] [ F9, 1250.0] [ R1, 25.0] [ R2, 12.5] [ xC12, 0.09375] [ xC4, 0.01] [ xC5, 0.02020202020202020202020202020202] [ xC6, 0.013123359580052493438320209973753] [ xC7, 0.013123359580052493438320209973753] [ xC8, 0.013123359580052493438320209973753] [ xC9, 0.015] [ xE4, 0.1] [ xE5, 0.075757575757575757575757575757576] [ xE6, 0.07874015748031496062992125984252] [ xE7, 0.07874015748031496062992125984252] [ xE8, 0.07874015748031496062992125984252] [ xH12, 0.65625] [ xH5, 0.01010101010101010101010101010101] [ xH9, 0.945] [ xN4, 0.78] [ xN5, 0.78787878787878787878787878787879] [ xN6, 0.8188976377952755905511811023622] [ xN7, 0.8188976377952755905511811023622] [ xN8, 0.8188976377952755905511811023622] [ xO4, 0.11] [ xO5, 0.085858585858585858585858585858586] [ xO6, 0.089238845144356955380577427821522] [ xO7, 0.089238845144356955380577427821522] [ xO8, 0.089238845144356955380577427821522] [ xOE5, 0.02020202020202020202020202020202] [ xOE9, 0.04] [ xOE12, 0.25]

But when I try to solve the same file with Matlab 2013b, an error is produced and no solution is obtained.

Please, any of you have experienced the same error? Any advice for avoiding it?

Thank you in advance

Salva