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    <font size="+1"><font face="Source Sans Pro">In followup to earlier
        post. here is what I tried:<br>
        <br>
        <font size="+1">1\ uninstall, complete reinstall of MikTeX
          (takes only 5-6 minutes with my network)<br>
          <br>
          <font size="+1">2\ try compiling the following MWE<br>
            <br>
            <font size="+1">\documentclass[11pt,letterpaper]{article}<br>
              <br>
              \usepackage{fontspec}<br>
              \setromanfont[Ligatures=TeX]{XITS}<br>
              \usepackage{unicode-math}<br>
              \setmathfont[math-style=ISO,bold-style=ISO,vargreek-shape=TeX]{XITS
              Math}<br>
              <br>
              <br>
              \begin{document}<br>
              <br>
              Lorem ipsum dolor sit amet, consectetur adipiscing elit.
              Praesent in tincidunt nulla. Donec quis laoreet est.
              Aenean vitae est felis, a venenatis magna. Mauris semper
              bibendum vulputate. Etiam bibendum quam ut erat rutrum
              consequat.<br>
              <br>
              \begin{equation}<br>
              \frac{dN}{dt}=rn\left(1-\frac{N}{K}\right)<br>
              \end{equation}<br>
              <br>
              \end{document} </font><br>
            <br>
            Comp<font size="+1">iles perfectly.<br>
              <br>
              <font size="+1">3\ fire up MkTeX updates -- update every<font
                  size="+1">thing (lua* an everythng else). What the
                  heck. ;-)<br>
                  <br>
                  <font size="+1">4\ MWE no longer c<font size="+1">ompile<font
                        size="+1">s. <font size="+1">Complaints</font>
                        about format. Try using MikTeX's <font
                          size="+1">format updating ut<font size="+1">ility
                            - doesn't work. Try <font size="+1">from
                              command line<br>
                              <br>
                            </font></font></font></font></font></font></font></font></font></font></font></font></font><br>
    <font size="+1"><font face="Source Sans Pro"><font size="+1"><font
            size="+1"><font size="+1"><font size="+1"><font size="+1"><font
                    size="+1"><font size="+1"><font size="+1"><font
                          size="+1"><font size="+1"><font size="+1">initexmf
                              --dump=lualatex
                              <br>
                              <br>
                              <font size="+1">Now I generate a new .fmt
                                file (so, the gui-based format update
                                utility doesn't sem to work, but doing
                                it from the command line did)<br>
                                <br>
                                <font size="+1">5\ try another compile
                                  of the MWE -- still fails, but with a
                                  more telling error messa<font
                                    size="+1">GE:<br>
                                    <br>
                                    <font size="+1"><font size="+1">luaotfload
                                        | db: Font names database not
                                        found, generating a new one.<br>
                                        <br>
                                        <font size="+1">Then it fails --
                                          unexpected condition.<br>
                                          <br>
                                          <font size="+1">If I comment
                                            out <br>
                                            <br>
                                          </font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font><br>
    <font size="+1"><font face="Source Sans Pro"><font size="+1"><font
            size="+1"><font size="+1"><font size="+1"><font size="+1"><font
                    size="+1"><font size="+1"><font size="+1"><font
                          size="+1"><font size="+1"><font size="+1"><font
                                size="+1"><font size="+1"><font
                                    size="+1"><font size="+1"><font
                                        size="+1"><font size="+1"><font
                                            size="+1"><font size="+1"><font
                                                face="Source Sans Pro"><font
                                                  size="+1"><font
                                                    size="+1"><font
                                                      size="+1">%\usepackage{fontspec}<br>
%\setromanfont[Ligatures=TeX]{XITS}<br>
%\usepackage{unicode-math}<br>
                                                      %\setmathfont[math-style=ISO,bold-style=ISO,vargreek-shape=TeX]{XITS
                                                      Math}<br>
                                                      <br>
                                                      <font size="+1">in
                                                        the MWE,
                                                        compiles fine. <font
                                                          size="+1">So,
                                                          the problem is
                                                          with fontspec
                                                          (or things
                                                          related to
                                                          it). <br>
                                                          <br>
                                                          <font
                                                          size="+1">If I
                                                          have a chance
                                                          tomorrow, I
                                                          might do a<font
                                                          size="+1">nother
                                                          complete
                                                          re-install,
                                                          and update
                                                          only fontspec
                                                          to see if it
                                                          is the problem<font
                                                          size="+1">...</font></font></font><br>
                                                        </font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font></font>
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