To make your server more stable

1. Remove any SNMP extensions in your system folder. I have found a case where SNMP polling, which usually happens around 12 am - 1 am, can cause the Open Transport SNMP code to die. Usually some NT box with some HP (?) printing software installed is on the network somewhere and it has SNMP polling turned on at 1:00 am every night.
2. Remove the OT AutoPush Support extension from your system folder. This is known bug in Open Transport that will cause the File Server to hang usually during heavy traffic on 100 mbit links. Does not seem to happen on slower links, but still worth removing. Unfortunately, TCP filtering will not work anymore. Try www.opendoor.com for another TCP filtering that may work
3. Turn off Sherlock Indexing on your server.
4. Check your users and groups file on a regular basis with UG first aid, or just rebuild it completely using my ASIP Save/Restore with XML export/import. This should also fix the 43 error that seems to crop up. Also fixes weird freezes when a particular user logs in, startup problems, etc. Actually checking the UG file is probably the first place to start when isolating a problem with your server.
5. Move to ASIP 6.3.x as soon as you can (unless your server is completely stable, then leave it alone) since it has all the latest fixes in it.
6. Check your server's HDs on a regular basis. Everyone has their favorite disk utility to use. Do this on a regular basis to catch disks going bad on you.
   

Give your server CPU lots and lots of RAM. This will help performance out quite a bit and will avoid any low memory bugs.

Optional
If you have hubs that support full/half, 10/100 enet and are using built in ethernet, consider using my Duplexer utility to "force" a particular speed. There have been several reports due to the ethernet auto-negotiate failing to correctly set its speed and resulting in terrible performance.