I've downloaded both part of grandia 2. I'm trying to combine both files but it isn't working. I put both parts into a folder and right click and select extract here. The files doesn't combine. Please help me. This is for the dreamcast emulator

This should probally be in GetYourRom discussion, but I'll answer.
Assuming you used the backup download links (considering the single disk links are down) you have to download 6 parts for disk 1 and 7 parts for disk 2.
Make sure you have the correct number of parts for each disk, then right click part 1 of the disk you want to extract and extract.
If it doesnt extract correctly right click part one again and select test archive, then tell me if it says any of the parts are corrupt.

There are only 2 parts to Grandia 2. I tested each part and they aren't any errors. Also I'm sorry for posting in the wrong area.

We are talking about this page here are we not-
http://www.get-your-rom.com/DREAMCAST-game.php?GAME_ID=158
or are you on a different page then that?

Grandia 2 - Disk 1 (U) iso / rom LINK BROKEN
Grandia 2 - Disk 2 (U) iso / rom LINK BROKEN

Backup Downloads
Disc 1: Part1 | Part2 | Part3 | Part4 | Part5 | Part6
Disc 2: Part1 | Part2 | Part3 | Part4 | Part5 | Part6 | Part7

There are two disks but there are 6 files needed to make disk one and 7 to make disk two.
So I would need to know what you downloaded before I can do anything else.

http://www.romulation.net/downloads/search/Dreamcast/grandia+2/
This one here. Should I try the parts you posted?

I suppose this is partly my fault for not asking first "where did you get them".
I just assumed since you were posting here on Vizzed that it was about our rom site, GetYourRom.
Sorry about the mix up.
First thing I'll mention is this "Vizzed is in no way related to or supports that site", so if it's a problem with the file you have to either get it elsewhere or ask them about it.

But despite that I'll post what I can that might help you out.
Acording to that sites page, each rar file is supposed to be a whole disk, so you should be able to just extract it.
Those rar files are not supposed to combine.
So "Grandia II Disc 1 of 2 (U)(ECHELON).rar" is all of the first disk, when you extract that you should get the files that make a file copy of a Dreamcast game, probally something like "Grandia II disc 1.cdi".
Or maybe... I think the other type Dreamcast might use is .img

Just in case you know nothing about Dreamcast emulation, read this guide.
https://www.vizzed.com/vizzedboard/thread.php?id=4630
The one about nullDC is most relevent to Dreamcast emulation.

And if their files dont work for you you can try the ones I linked to in the last post.

Error after error another error. I never knew that it was supposed to be that way, sorry. I tried your amazing guide for nullDC, everything was going well untill I loaded disc one. I attempted to start but each time it did, it crashed. Sorry for all the trouble >.

You can always try the link I gave you to get your rom, the backup downloads in 6 and 7 parts are the only ones that work, and for those they need to combine.
Unfotunately I cant do any further testing on my end as I'm out of hard drive space and cant download much more.
Oh and I'll look into the other thing, RE PM, and let you know

Alright, thanks a lot.