There are many related questions and answers. I looked at Installing EB Garamond for pdfLaTeX (encore) and tried the lua answer there. lualatex from a freshly instlled Miktex on this MWE
\documentclass{memoir}
\usepackage{fontspec}
\setmainfont[Ligatures=TeX]{EB Garamond}
\begin{document}
The Quick Brown Fox Jumps Over The Lazy Dog. 0123456789
\emph{Try italics.} \\
{\bfseries Try bold face} \\
{\scshape Try small caps} \\
\end{document}
produces
starting package maintenance...
installation directory: C:\Users\eb\AppData\Roaming\MiKTeX\2.9
package repository: http://mirrors.rit.edu/CTAN/systems/win32/miktex/tm/packages/
lightweight database digest: 8a9d030e8c8fa3aaa59a4f1bbb445ea5
going to download 8096508 bytes
going to install 181 file(s) (1 package(s))
downloading http://mirrors.rit.edu/CTAN/systems/win32/miktex/tm/packages/tipa.tar.lzma...
8096508 bytes, 765.27 KB/Sec
extracting files from tipa.tar.lzma...
======================================================================
(C:/Users/eb/AppData/Roaming/MiKTeX/2.9//tex/latex/tipa/t3enc.def(save: C:/Users
/eb/AppData/Local/MiKTeX/2.9/luatex-cache/generic/fonts/otf/lmromanslant10-regul
ar.lua)(save: C:/Users/eb/AppData/Local/MiKTeX/2.9/luatex-cache/generic/fonts/ot
f/lmromanslant10-regular.luc)(save: C:/Users/eb/AppData/Local/MiKTeX/2.9/luatex-
cache/generic/fonts/otf/lmroman10-italic.lua)(save: C:/Users/eb/AppData/Local/Mi
KTeX/2.9/luatex-cache/generic/fonts/otf/lmroman10-italic.luc)(save: C:/Users/eb/
AppData/Local/MiKTeX/2.9/luatex-cache/generic/fonts/otf/lmroman10-bold.lua)(save
: C:/Users/eb/AppData/Local/MiKTeX/2.9/luatex-cache/generic/fonts/otf/lmroman10-
bold.luc) ("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/euenc/eu2lmss.fd")(save:
C:/Users/eb/AppData/Local/MiKTeX/2.9/luatex-cache/generic/fonts/otf/lmsans10-re
gular.lua)(save: C:/Users/eb/AppData/Local/MiKTeX/2.9/luatex-cache/generic/fonts
/otf/lmsans10-regular.luc))
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/graphics/graphicx.sty"
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/graphics/keyval.sty")
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/graphics/graphics.sty"
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/graphics/trig.sty")
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/00miktex/graphics.cfg")
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/pdftex-def/pdftex.def"
("C:/Program Files (x86)/MiKTeX 2.9/tex/generic/oberdiek/ltxcmds.sty")
("C:/Program Files (x86)/MiKTeX 2.9/tex/generic/oberdiek/pdftexcmds.sty"
(C:/Program Files (x86)/MiKTeX 2.9/scripts/oberdiek/pdftexcmds.lua))))))
("C:/Program Files (x86)/MiKTeX 2.9/tex/latex/fontspec/fontspec.cfg")))
luaotfload | cache : No lookup cache, creating empty.
luaotfload | db : Reload initiated; reason: "unresolved font name: 'ebgaramond12
'"
luaotfload | db : Font index saved
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!
! fontspec error: "font-not-found"
!
! The font "EBGaramond12" cannot be found.
The Miktex package manager says ebgaramond is there.
The fontspec documentation is pretty dense.
I've looked at http://docs.miktex.org/manual/advanced.html#psfonts, to no avail.I can't examine updmap.cfg because windows 7 search doesn't find it and I don't know where to look by hand.
Edit: As per @UlrikeFischer comment:
eb@7J8B8W1 ~
$ luaotfload-tool -u -vv
...
luaotfload | util : Task completed successfully
eb@7J8B8W1 ~
$ luaotfload-tool --alias=luaotfload-tool --find="ebgaramond"
luaotfload | resolve : Cannot find "ebgaramond".
Edit: Progress! \usepackage{ebgaramond} works with pdflatex. (The bold face doesn't, but according to a comment elsewhere by @egreg I shouldn't want it anyway.)
Perhaps I should move my whole project from luatex to pdftex.

\setmainfont{Arial}? – Ulrike Fischer Jun 10 '14 at 15:24\setmainfont{EB Garamond 12}work? – cfr Jun 10 '14 at 17:31ebgaramondpackage? In particular, do you have only the type1 fonts (pfbfiles) or do you have opentype (otf) as well? – cfr Jun 10 '14 at 21:00ebgaramondusing pdfTeX? If MiKTeX can't find the type1 versions either, that might suggest that the package just didn't get installed properly at all. – cfr Jun 11 '14 at 01:22luaotfload-tool -u -vv) (if it hangs somewhere you will have to blacklist the fonts). Then check withluaotfload-tool --alias=luaotfload-tool --find="ebgaramond"if the font is found. – Ulrike Fischer Jun 11 '14 at 06:48\usepackage{ebgaramond}should work directly (naturally without fontspec + setmainfont). – Ulrike Fischer Jun 11 '14 at 13:33