Delete similar entries in ms access
===

I have a ms access mdb-file like this:

    table Main:
    
     int recordID, int status, int placement, bool @private, string category, string note, string description, string dueDate, bool completed, int priority, byte[] blob, bool repeatOnCompleteDate, string completeDate, bool alarmSet, string alarmTime, int alarmAdvance, string repeatStartDate, string repeatInfo

I would like to remove duplicate entries where description+note is the same so only one entry with the same description+note content remains. If there are two or more duplicates where some entries' category is 0(beware it's a string) remove this rather than the one whose category does not equal zero.

Fi.

    Desc - Note - Cat
    Hello - Test - 0
    Hello - no - 3
    Hello - Test - 0
    Hello - Test - 4
    Hello - Test - 0

Then one single Desc Hello with Note Test and with Category 4 should remain.

I found 

    delete from MyTable
    where uniqueField not in
    (select min(uniqueField) from MyTable T2
    where T2.dupField=MyTable.dupField)

converted it to

    delete from Main where Category not in (select min(Category) from Main T2 where T2.Description=Main.Description)

but that does not work.

Which MSACCESS SQL Command do you recommend?