title: Issues using xlsx package to insert data from R to excel
body: <p>I´m trying to create a new excel workbook from R to save a few small datasets using xlsx package. For some reason it was working fine, but i´m unable to do it again.</p>
  
  <p><strong>Code to create a new workbook</strong></p>
  
  <pre><code>library("xlsx")
  library("xlsxjars")
  library("rJava")
  
  file &lt;- "marca_imei.xlsx"
  wb &lt;- loadWorkbook(file)
  
  # The error:
  # Error in .jcall("RJavaTools", "Ljava/lang/Object;", "invokeMethod", cl,  : 
  #  java.lang.IllegalArgumentException: Your InputStream was neither an OLE2 stream, nor an OOXML stream
  </code></pre>
  
  <p>I´ve searched for an answer but it seems people are having the same error when importing data from excel.
  I´ve tried what was recommended but it didn´t work. Here are some links for future searchers:</p>
  
  <ul>
  <li><a href="http://r.789695.n4.nabble.com/Read-shortcuts-of-MS-Excel-files-through-R-td4677020.html" rel="noreferrer">http://r.789695.n4.nabble.com/Read-shortcuts-of-MS-Excel-files-through-R-td4677020.html</a></li>
  <li><a href="http://r.789695.n4.nabble.com/Problem-with-xlsx-package-td3298470.html" rel="noreferrer">http://r.789695.n4.nabble.com/Problem-with-xlsx-package-td3298470.html</a></li>
  </ul>
  
  <p><code>sessionInfo()</code>:</p>
  
  <pre><code>locale:
  [1] LC_COLLATE=Spanish_Spain.1252  LC_CTYPE=Spanish_Spain.1252    LC_MONETARY=Spanish_Spain.1252
  [4] LC_NUMERIC=C                   LC_TIME=Spanish_Spain.1252    
  
  attached base packages:
  [1] stats     graphics  grDevices utils     datasets  methods   base     
  
  other attached packages:
   [1] xlsx_0.5.5             xlsxjars_0.6.0         RJDBC_0.2-3            rJava_0.9-6           
   [5] DBI_0.2-7              slidifyLibraries_0.3.1 slidify_0.4            knitr_1.5             
   [9] devtools_1.4.1         scales_0.2.3           ggplot2_0.9.3.1        data.table_1.8.11     
  [13] reshape2_1.2.2        
  
  loaded via a namespace (and not attached):
   [1] colorspace_1.2-4   dichromat_2.0-0    digest_0.6.4       evaluate_0.5.1     formatR_0.10      
   [6] grid_3.0.2         gtable_0.1.2       httr_0.2           labeling_0.2       markdown_0.6.3    
  [11] MASS_7.3-29        memoise_0.1        munsell_0.4.2      parallel_3.0.2     plyr_1.8          
  [16] proto_0.3-10       RColorBrewer_1.0-5 RCurl_1.95-4.1     stringr_0.6.2      tools_3.0.2       
  [21] whisker_0.3-2      yaml_2.1.10     
  </code></pre>