You have at least one rule missing. For example, in
Text1=
'ABNAGENDRACSURENDRADJITHENDRAXNARENDRABVEERNDARAXDRMNDRAXRVINDRABNAGENDRACSURENDRADJITHEN'
The first A not followed by a B, C or D is "AGENDR". Why is that "A" excluded?
SQL DBA,SQL Server MVP(07, 08, 09) A socialist is someone who will give you the shirt off *someone else's* back.