\[ \boxed { {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) =-{\frac {{\frac {\rm d}{{\rm d}x}}y \left ( x \right ) }{1+x}}-{\frac {y \left ( x \right ) }{x \left ( 1+x \right ) ^{2}}}=0} \]
Mathematica: cpu = 0.028504 (sec), leaf count = 29 \[ \left \{\left \{y(x)\to \frac {c_1 x}{x+1}+\frac {c_2 (x \log (x)-1)}{x+1}\right \}\right \} \]
Maple: cpu = 0.031 (sec), leaf count = 26 \[ \left \{ y \left ( x \right ) ={\frac {x{\it \_C1}}{1+x}}+{\frac {{\it \_C2}\, \left ( x\ln \left ( x \right ) -1 \right ) }{1+x}} \right \} \]