title: Merging two excel files in c# without using interop
body: <p>I have to merge two excel files containing one sheet in each of them and I have to generate a third file containing two sheets corresponding to the two original sheets. </p>
  
  <p>This task can be done using "interop" and the code works but when the same code is run in a system that does not contain MS Office, the process fails and an error comes up. </p>
  
  <p>Can you please guide me as to what dll files to be included or how this merging could be done without using interop?</p>
  
  <p>Thanks in advance.</p>