During complete process of Tan Registration , It is not mandatory to have File Merger Software with you. It depends upon your fvu file size which is required by you. It means in case you have 400 deductees in your data and request for consolidated statement has been made by you. You will receive only one file with the extension code .tds. As you have received one file, there is no need of File Merger Software. However your fvu file may be 3000 deductees. In such cases NSDL will provide .tds(FVU files) in multiple files. Then there is no other source to merge files in a single file. This software is also known in the name of FMU (File Merger Utility). NSDL provide it complete free at their TIN website or under the option "Tan Registration " in download section. Picture view is given as under :-
Complete procedure to Download "File Merger Software" and installation is given here. Click Here
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