How to programmatically restore the XLS file that was modified by a thirdparty tool
<p>We are in the process of migrating the documents from AppXTender ( a EMC Documentum tool ) to another system.</p>

<p>I took a XLS file from AppXtender physical store ( the tool have renamed the .XLS file to .BIN ) and I knew its an excel file I tried renaming it to .XLS but the file is not opening as excel.
I learnt that the file is been modified by the AppXtender with some content like, "FFL 1.0 followed by the original file name.XLS". 
When I open the excel in a notepad I could see this in the first line and there are couple of more lines with some text like "Embedded" and with some number.</p>

<p>If I manually remove those lines and save the file and still the file is not opening as excel. </p>

<p>What are these custom texts? how do i programmatically (C#) remove them from the excel file and restore as the proper excel file? </p>

<p>Thanks!
Karthik</p>