What are the commands to get some more information about err-disabled ports.
(For example to find out what was the reason for err disabling)
Rack1SW1(config-if)#do show int status
Port Name Status Vlan Duplex Speed Type
Fa0/1 err-disabled 18 auto auto 10/100BaseTX
Fa0/2 connected 26 a-full a-100 10/100BaseTX
I believe this is the command you are looking for - at least on low to mid range switches...
Switch#sh port-security interface fa0/1
Port Security : Disabled
Port Status : Secure-down
Violation Mode : Restrict
Aging Time : 0 mins
Aging Type : Absolute
SecureStatic Address Aging : Disabled
Maximum MAC Addresses : 2
Total MAC Addresses : 0
Configured MAC Addresses : 0
Sticky MAC Addresses : 0
Last Source Address:Vlan : 0000.0000.0000:0
Security Violation Count : 0
Eventhough is one of the most common the err-disable feature is not only for port-security feature, but for 802.1X, PAgP, EtherChannel, flapping interfaces, and a lot more of error conditions on your switch. Check what kind of feature is enabled that caused the error condition on your switch.
Check this out to help you to understand how troubleshoot err-disable port.