I will give you 2 ways.
Here is the first:
-----1st Way-----
Make a folder with all the splitted files in, like "C:\iso\all files here"
Then press Start-->Run-->cmd-->enter
This will start up command prompt.
We will now go to the folder with our splitted files, type:
cd C:\iso\
This will take you to that folder.
Now lets have a look whats in it, type:
dir
You can see some information now.
We will now make it put all the splitted files back together, type:
copy/b "My first file"+"My second file"+"My third file" (...) last file.iso
Let me explain that. We type copy/b so it will copy all files, then we put our first file + second +third, go on with more if neccesary. Thats what i mean with (...), so dont type that! Then i typed last file.iso, thats the latest file.
Here is the code explained in words: Copy file my first file and my second file and my third file and rename them to last file.iso.
Hope you unnderstand that part!
Let your pc run now, and in a few min, the files should be joined.
-----Stop 1st way-----
I will give you another way, because this one only works on the C:\ drive
-----2nd Way-----
download this: http://cs.ulm.edu/~jself/jmenc/rejoin_v2.exe
Install it and remember the directory!
Go to the directory, and you will see a couple files and 2 folders. Start the file called: rejoin.jar
then go to the folder with all the files in, ONLY THE FILES. no other. Click open. And wait a few mins. Then it should have put all the files in that folder together in a file called: LATEST.ISO (i think, but its all the same eh)
-----Stop 2nd Way-----
So actually the 2nd way is easyer and better. Hope it helped!

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