As Lynn and Matt pointed out, adding a new column and updateing will solve your problem. My example assumes you are using some version of Query Analyzer where you are able to create SQL and execute it.

There are two ways to approach this. The first way is the easiest.

1)

alter table TABLE1

alter column COL1 datetime

Where TABLE1 is the particular table in questions and

Where COL1 is the name of the column containing all of your nvarchar(50) data.

Done.

2)

I am creating a dummy table table to simulate your table of data.

create table tt

(

col1 nvarchar(50)

)

I am inserting rows with data that have a datatype of nvarchar(50) to simulate your data.

insert tt

select '01/01/2008' union

select '01/02/2008' union

select '01/03/2008' union

select '01/04/2008' union

select '01/05/2008' union

select '01/06/2008' union

select '01/07/2008'

I am adding the new column of datatype datetime that Lyn and Mat were talking about.

alter table tt

add NewDateCol datetime

Now I fire an update statement to produce values of type datetime using the nvarchar data.

update tt

set NewDateCol = cast(col1 as datetime)

I am selecting the data to view and verify.

select * from tt

I hope this works.