Unable to Read "XLSX" file using R

1.   If you have RStudio , check the below for the existence of package "xlsx" and "xlsxjars"

If the packages does not exist ,
              Click on "Install Packages"
               Search for the package and install the components .

2.  After having installed the packages , click on the checkbox as given above . The below is how you should see after the package has been installed

3.  You might see Java related problem when you try to load your excel file . See below 

Loading required package: rJava

library(rJava)

Error : .onLoad failed in loadNamespace() for ‘rJava’, details:

call: fun(libname, pkgname)

error: JAVA_HOME cannot be determined from the Registry

To resolve these issue , download the 64 BIT latest JAVA (jre-7u15-windows-x64.exe) from Oracle's website 

http://www.oracle.com/technetwork/java/javase/downloads/index.html

you will need to login into the website using your user and password .

4.   In the windows machine , the below is the next step that you need to follow 

Change/Add the JAVA_HOME to the location where it has been installed.

The location might differ for 32 and 64 bit as given below . Put the appropriate one in the system variable list

JAVA_HOME='C:\\Program Files\\Java\\jre7'  # for 64-bit version

JAVA_HOME='C:\\Program Files (x86)\\Java\\jre7' # for 32-bit version

5.  Re-Start your R-Studio 

Enjoy !! You should now be able to see the data being pulled correctly from Excel .