Most of the files that you see of the form .001, .002 are split using hjsplit. To join them you just need to usehjsplit.Download click here. You do not have to install HJSplit. Just extract ‘hjsplit.zip’ which you woulddownload and double click on HJSplit.exe to start HJSplit. After thar, the main window of HJSplit will appear.
1)To join the files, click on ‘Join’:
2)In the new window that appears, click on input file:
3)In the new window, select only the first file of the files that we would like to join (it automatically shows only .001 file), so fired.avi.001 in this case, and click on ‘Open’ after that.
4)Click on ‘Start’:
5)Now HJSplit will join the file, in few seconds. When it is finished you will see this message:
The files have been successfully joined! The joined output file is stored in the default location, which would be same as the location of your input .001 file. Enjoy 
