If you want to install Arachne on server (ie. drive S:), but workstations have some local disk space available (ie. drive C:) and each user has it's own home direcotry (ie. H:), try to setup Arachne options like this:
Cache path = C:\CACHE\
Mail path = H:
Download path = A:\
Cache index = C:\CACHE\tohleuz.mam
History file = H:tadyjsem.byl
Don't forget to create directory C:\CACHE!
If workstations use different SCGA cards, run Arachne from C:\ARACHNE - Arachne always saves video card information (AACHNE.PCK) in current directory. But make sure each ARACHNE.PCK sholud use same history file (ie. C:\ARACHNE\tadyjsem.byl