<html><head></head><body><div class="ydp6f92181dyahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div dir="ltr" data-setdir="false"><div><div dir="ltr" data-setdir="false" style="color: rgb(0, 0, 0); font-family: Helvetica Neue, Helvetica, Arial, sans-serif; font-size: 16px;">Dear wannier90 users, </div><div dir="ltr" data-setdir="false" style="color: rgb(0, 0, 0); font-family: Helvetica Neue, Helvetica, Arial, sans-serif; font-size: 16px;">I am using wannier90-3.0.0. For calculating wannier90 band structure, i got this error "<b>Error reading u_matrix_opt from wannier90.chk in param_read_chkpt"</b>. I don't know how to solve this error. I need your help to fix this error.</div><div dir="ltr" data-setdir="false" style="color: rgb(0, 0, 0); font-family: Helvetica Neue, Helvetica, Arial, sans-serif; font-size: 16px;">Thank You</div></div><br></div></div></body></html>