alter PROCEDURE sp_decrypt(@objectName varchar(50))
AS
begin
begin transaction
declare @objectname1 varchar(100)
declare @sql1 nvarchar(4000),@sql2 nvarchar(4000),@sql3 nvarchar(4000),@sql4 nvarchar(4000),@sql5 nvarchar(4000),@sql6 nvarchar(4000),@sql7 nvarchar(4000),@sql8 nvarchar(4000),@sql9 nvarchar(4000),@sql10 nvarchar(4000)  
DECLARE  @OrigSpText1 nvarchar(4000),  @OrigSpText2 nvarchar(4000) , @OrigSpText3 nvarchar(4000), @resultsp nvarchar(4000)
declare  @i int , @t bigint
declare @m int,@n int,@q int
set @m=(SELECT max(colid) FROM syscomments  WHERE id = object_id(@objectName))
set @n=1
--get encrypted data
create table  #temp(colid int,ctext varbinary(8000))
insert #temp SELECT colid,ctext FROM syscomments  WHERE id = object_id(@objectName)
set @sql1='ALTER PROCEDURE '+ @objectName +' WITH ENCRYPTION AS '
--set @sql1='ALTER PROCEDURE '+ @objectName +' WITH ENCRYPTION AS '
set @q=len(@sql1)
set @sql1=@sql1+REPLICATE('-',4000-@q)
select @sql2=REPLICATE('-',4000),@sql3=REPLICATE('-',4000),@sql4=REPLICATE('-',4000),@sql5=REPLICATE('-',4000),@sql6=REPLICATE('-',4000),@sql7=REPLICATE('-',4000),@sql8=REPLICATE('-',4000),@sql9=REPLICATE('-',4000),@sql10=REPLICATE('-',4000)


exec(@sql1+@sql2+@sql3+@sql4+@sql5+@sql6+@sql7+@sql8+@sql9+@sql10)
while @n<=@m
 begin
  SET @OrigSpText1=(SELECT ctext FROM #temp  WHERE colid=@n)
  set @objectname1=@objectname+'_t'
  SET @OrigSpText3=(SELECT ctext FROM syscomments WHERE id=object_id(@objectName) and colid=@n)
  if @n=1
  begin
  SET @OrigSpText2='CREATE PROCEDURE '+ @objectName +' WITH ENCRYPTION AS '--
  set @q=4000-len(@OrigSpText2)
  set @OrigSpText2=@OrigSpText2+REPLICATE('-',@q)
  end
  else
  begin
  SET @OrigSpText2=REPLICATE('-', 4000)
  end
  --start counter
  SET @i=1
  --fill temporary variable
  SET @resultsp = replicate(N'A', (datalength(@OrigSpText1) / 2))
  
  --loop
  WHILE @i<=datalength(@OrigSpText1)/2
  BEGIN
  --reverse encryption (XOR original+bogus+bogus encrypted)
  SET @resultsp = stuff(@resultsp, @i, 1, NCHAR(UNICODE(substring(@OrigSpText1, @i, 1)) ^
                                  (UNICODE(substring(@OrigSpText2, @i, 1)) ^
                                  UNICODE(substring(@OrigSpText3, @i, 1)))))
      SET @i=@i+1
  END
  --drop original SP
  --EXECUTE ('drop PROCEDURE '+ @objectName)
  --remove encryption
  --preserve case
  SET @resultsp=REPLACE((@resultsp),'WITH ENCRYPTION', '')
  SET @resultsp=REPLACE((@resultsp),'With Encryption', '')
  SET @resultsp=REPLACE((@resultsp),'with encryption', '')
  IF CHARINDEX('WITH ENCRYPTION',UPPER(@resultsp) )>0 
    SET @resultsp=REPLACE(UPPER(@resultsp),'WITH ENCRYPTION', '')
  --replace Stored procedure without enryption
  print @resultsp
  --execute( @resultsp)
  set @n=@n+1
 end
   
drop table #temp
rollback transaction
end

------解决方案--------------------
SQL code

--下面是网上一个很流行的解密过程   
    
  create     PROCEDURE   sp_decrypt(@objectName   varchar(50))   
    
  AS   
    
  begin   
    
  set   nocount   on   
  begin   tran   
    
  declare   @objectname1   varchar(100),@orgvarbin   varbinary(8000)   
    
  declare   @sql1   nvarchar(4000),@sql2   varchar(8000),@sql3   nvarchar(4000),@sql4   nvarchar(4000)   
    
  DECLARE   @OrigSpText1   nvarchar(4000),   @OrigSpText2   nvarchar(4000)   ,   @OrigSpText3   nvarchar(4000),   @resultsp   nvarchar(4000)   
    
  declare   @i   int,@status   int,@type   varchar(10),@parentid   int   
    
  declare   @colid   int,@n   int,@q   int,@j   int,@k   int,@encrypted   int,@number   int   
    
  select   @type=xtype,@parentid=parent_obj   from   sysobjects   where   id=object_id(@ObjectName)   
    
    
    
  create   table   #temp(number   int,colid   int,ctext   varbinary(8000),encrypted   int,status   int)