title: fatal error: Rcpp.h: No such file or directory
body: <p>I'm just trying to get started with Rcpp and I keep running into this error no matter what I do.</p>
  <pre><code>&gt; library(&quot;Rcpp&quot;)
  &gt; evalCpp(&quot;2 + 2&quot;)
  &quot;C:/rtools40/mingw64/bin/&quot;g++ -std=gnu++11  -I&quot;C:/PROGRA~1/R/R-40~1.2/include&quot; -DNDEBUG   -I&quot;//ad.uws.edu.au/dfshare/HomesBLK90946112/My Documents/R/win-library/4.0/Rcpp/include&quot; -I&quot;C:/Users/90946112/AppData/Local/Temp/Rtmp0Q7m7J/sourceCpp-x86_64-w64-mingw32-1.0.5&quot;        -O2 -Wall  -mfpmath=sse -msse2 -mstackrealign -c file45bc2c9438a5.cpp -o file45bc2c9438a5.o
  file45bc2c9438a5.cpp:1:10: fatal error: Rcpp.h: No such file or directory
   #include &lt;Rcpp.h&gt;
            ^~~~~~~~
  compilation terminated.
  make: *** [C:/PROGRA~1/R/R-40~1.2/etc/x64/Makeconf:229: file45bc2c9438a5.o] Error 1
  Error in sourceCpp(code = code, env = env, rebuild = rebuild, cacheDir = cacheDir,  : 
    Error 1 occurred building shared library.
  </code></pre>
  <p>To check that everything is set up correctly, I have run the following checks:</p>
  <pre><code>&gt; find_rtools()
  [1] TRUE
  &gt; find.package('Rcpp')
  [1] &quot;\\\\ad.uws.edu.au/dfshare/HomesBLK$/90946112/My Documents/R/win-library/4.0/Rcpp&quot;
  </code></pre>
  <p>and</p>
  <pre><code>&gt; find_rtools()
  [1] TRUE
  &gt; find.package('Rcpp')
  [1] &quot;\\\\ad.uws.edu.au/dfshare/HomesBLK$/90946112/My Documents/R/win-library/4.0/Rcpp&quot;
  &gt; Sys.getenv(&quot;PATH&quot;)
  [1] &quot;C:\\rtools40\\usr\\bin;C:\\Program Files\\R\\R-4.0.2\\bin\\x64;C:\\Rtools\\bin;C:\\ProgramData\\Oracle\\Java\\javapath;C:\\WINDOWS\\system32;C:\\WINDOWS;C:\\WINDOWS\\System32\\Wbem;C:\\WINDOWS\\System32\\WindowsPowerShell\\v1.0\\;C:\\WINDOWS\\System32\\OpenSSH\\;C:\\Program Files\\Git\\cmd;C:\\Users\\90946112\\AppData\\Local\\Microsoft\\WindowsApps;&quot;
  &gt; has_devel()
  Your system is ready to build packages!
  </code></pre>
  <p>I've seen so many questions on here for similar problems but none for Rtools40- which has a different file path- and none have helped. I have tried using an older version of R and Rtools. I've also uninstalled and reinstalled both.</p>
  <p>Please help!</p>