Best Backup for Small Business File Server!

Hello,

I work in a Architects office, we have a small network setup with Exchange Server and a File Server Machine. Our File Server is 640GB and it is almost 90% full, we used to have an IT guy but now he is gone.

It is very important for us to setup a backup system. Our network is run as follows:

1. Domain server,
2. Exchange Server
3. File Server (640GB)
4. 10-12 computers.

So what would be the best/cheap option for us to create a automatically backup of our file server. I was thinking in Setup a RAID 1, configuration in one of our computers with 2-2TB hardrives and get some software to backup the info regularly there.

We have not money to spend and we want to be able to use the hardware we already have?

Any help will be appreciated.

The Data is store in the Local Server, about 640GB.
-We are planing to backup to a local machine, this local machine will have 2-1TB regular hard drives in RAID 1 configuration. (The system we plan to use is a good machine with Win 7, I7 processor and 8gb memory).
-We also have a external hard drive that I can keep @ home and bring it only to the office twice a month for backup.

-As for the storage capacity, I have the ok to buy couple of hard drives to make the backup work.

I don't really know how the IT guy used to back up the files, all I know that our server crash about a year a go and we all restore our files from an external hard drive, it was a mess because there were duplicated files within the same folders, I guess once we rename a file it will backup that file and the original, !!but it was the same file, just different name!!


Thanks a lot for your help

Thanks, i will look into that, so I guess having a RAID DRIVES in a local machine connected to the server will do the trick, what about software,
Is there a good software that only backups the modified, new files?
Or everytime it will need to make an image of our server files?, this second option looks very demanding, its 600gb of info that will be backup everytime is schedule.

I will prefer some kind of software that only backups modified/new files.

Thanks

Thanks for the responds, as far as I know now.
1. Yes I can backup our network drive in one of our local machines.
2. A RAID 1 setup will do the work for now, we have no money to spend in additional drives.
3. I am not too much interested in creating a backup/image of the server OS. All I care is the folders and files on the network drive. Our server has a harddrive that holds the microsoft windows server OS and a RAID configuration for our network drive) all I care is to backup these files and folders.
3. Please I need a strong recommendation of what software to use to backup the files and folder from the network drive. This will be do from the local machine wih the new RAID 1.
I heard about read about the incremental backups (!!! this is what i want) but he software is to expensive, norton, acronis, etc. over $600. Is there something cheaper?

Thanks

See above and

Something else, our info is about 600gb. Ee have 10 stations, we handle a lot of info in a daily basis, Cad files, pictures and revit files, we can easily modify 20-30gb of data everyday.

Synctoy looks like a option, bu it seems to be used for desktops mostly.
Right now we use a external hard drive but its a pain in the ass, we get a lot of errors trying to copy big folders, 20gb, errors like the path is too long, and/or the file name.
Our office require to create a lot of subfolders and hundreds of files.

Thanks