You might be thinking the same. I'm only going to make some general comments here. I'm not familiar with your software. I'm making some assumptions also. Drive C: is primarily running the OS and any additional programs in a small office environment of perhaps 5-15 terminals. Is this correct? In generally what business are you in?
When it runs out of space it will refuse further additions. It's that simple.
Again this is an assumption the primary drive is about 60GB? If so, way to small.
Reactions.........Time to up grade the system, all of it, including the OS. In particular the primary drive.
There maybe a work around however. New drives could be created on F; these could be mounted to the C; drive to enable additional programs to be added. This might work but will be efficient perhaps slow. This would be only a short term solution for as data is added the system you will again run out of space and again up grades will be needed
Should you decide to upgrade use Raid drives that will allow more flexibility.
This software might also be of some use to you.
http://support.microsoft.com/kb/940439/en-us
Again these are just some general comments and suggestions you would need more input before proceeding with any changes.
Perhaps a professional consultant should be contracted to review your system but I wouldn't wait to long.
We are using MS Win Server 2003 for SBS SP2. Our C Drive is left with 17% Free Space (6.59GB). Almost all our data files, including email, are kept in F Drive, which is left with 71% Free Space (162GB). What will happen if our C Drive one day goes out of free disk space? Or is there any way that I can move some space from F Drive to C Drive? What shall we do now?

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