I created the TXT record in my.domain.com.

my.domain.com. IN TXT "v=spf1 +ip4: +mx +a:mail -all"

Now the SPF is working for email, but some users are complaining about their
access to internal websites. For a few users they are having problems
accessing the Intranet because it's query the internet instead. Does my TXT
record above look correct? The problem started happening after I added the
SPF record. Please help thanks. Also note the users that are having the most
problem are located on a different subnet. These users are using Microsoft
DNS and our NetWare DNS servers are in their forwarder. It worked before the
SPF record changes.