  We have searched for exotic neutrino-electron interactions that could be
produced by a neutrino millicharge, by a neutrino magnetic moment, or by dark
photons using solar neutrinos in the XMASS-I liquid xenon detector. We observed
no significant signals in 711 days of data. We obtain an upper limit for
neutrino millicharge of 5.4$\times$10$^{-12} e$ at 90\% confidence level
assuming all three species of neutrino have common millicharge. We also set
flavor dependent limits assuming the respective neutrino flavor is the only one
carrying a millicharge, $7.3 \times 10^{-12} e$ for $\nu_e$, $1.1 \times
10^{-11} e$ for $\nu_{\mu}$, and $1.1 \times 10^{-11} e$ for $\nu_{\tau}$.
These limits are the most stringent yet obtained from direct measurements. We
also obtain an upper limit for the neutrino magnetic moment of
1.8$\times$10$^{-10}$ Bohr magnetons. In addition, we obtain upper limits for
the coupling constant of dark photons in the $U(1)_{B-L}$ model of
1.3$\times$10$^{-6}$ if the dark photon mass is 1$\times 10^{-3}$ MeV$/c^{2}$,
and 8.8$\times$10$^{-5}$ if it is 10 MeV$/c^{2}$.
