title: Error when using readxl: 'exdir' does not exist
body: <p>I am trying to use readxl::read_excel to import tabular data from an excel spreadsheet (.xlsx and .xls) into R. I have had success with this function when reading spreadsheets from Desktop, but I am having trouble reading from my Documents folder now.  </p>
  
  <p>I tried reading both .xlsx and .xls formats of the same file and got 2 different error messages. </p>
  
  <pre><code># Check the working directory
  [1] "\\\\isdowfsv04/D100Home/e525902"
  
  # Read .xlsx
  specs &lt;- read_excel("Class Specs Sept 2016.xlsx")
  
  Error: 'exdir' does not exist
  
  # Read .xls
  specs &lt;- read_excel("Class Specs Sept 2016.xls")
  
  Error: path[1]="\\isdowfsv04/D100Home/e525902/Class Specs Sept 2016.xls": Access is denied
  </code></pre>
  
  <p>The second message made me think I don't have permission to read/write data here, but I create folders/files here all the time. I have even used another R library, readr package, to import .csv files from this same directory. </p>
  
  <pre><code># Using readr to import .csv version of the file works fine.
  specs &lt;- read_csv("\\\\isdowfsv04/D100Home/e525902/Class Specs Sept 2016.csv")
  </code></pre>
  
  <p>Based on other posts I've seen, it seems like a permission issue, but it's unclear to me how to fix it.</p>
  
  <p>I tried using Sys.setenv() to change the temporary folders location to somewhere I know I have permission to write (i.e., Desktop) because I thought readxl used these paths when reading the data. But that didn't work because I got the exact same error messages.</p>
  
  <pre><code>Sys.getenv(c("TEMP", "TMP"))
                                        TEMP                                        TMP 
  "C:\\Users\\e525902\\AppData\\Local\\Temp"     "C:\\Users\\e525902\\AppData\\Local\\Temp"
  
  # Change temp file paths to the Desktop
  Sys.setenv(TEMP = "C:\\Users\\e525902\\Desktop")
  Sys.setenv(TMP = "C:\\Users\\e525902\\Desktop")
  </code></pre>
  
  <p>I am using a PC at work and the Documents folder is actually a network drive. I have used read_excel to import .xlsx files from other network folders, but this one is giving me trouble. Below is more information on the system I'm using.</p>
  
  <pre><code>Sys.info()
  sysname                      release                      version 
                 "Windows"                      "7 x64" "build 7601, Service Pack 1" 
                  nodename                      machine                        login 
             "10004053WDT"                     "x86-64"                    "e525902" 
                      user               effective_user 
                 "e525902"                    "e525902"
  
  search()
   [1] ".GlobalEnv"        "package:readr"     "package:readxl"    "tools:rstudio"     "package:stats"    
   [6] "package:graphics"  "package:grDevices" "package:utils"     "package:datasets"  "package:methods"  
  [11] "Autoloads"         "package:base"
  
  # R version
  version$version.string
  version.string R version 3.2.5 (2016-04-14)
  </code></pre>