I have a query from which I want to turn into a view:

SELECT * FROM `telefoonnummers`
WHERE `Afdeling` IN
(SELECT `Afdeling`
FROM
(
SELECT @a:=@a+1 as 'a'
,`Afdeling`
FROM `Afdeling-telefoon`
JOIN (SELECT @a:=0) x
ORDER BY `Afdeling`
) y WHERE mod(a,2) = 0) ORDER BY `Afdeling`, `Naam`

The only problem is I cant make a view out of this. It says it is not possible.

It returns:
#1349 - View's SELECT contains a subquery in the FROM clause

Any ideas how I could turn this into a view (or stored procedure maybe)?

Instead of turning it into a view, turn it into a stored procedure (MySQL 5.0.0 or higher). It can still return the resultset you want to see, and it shouldn't complain about the subquery.

I use MySQL > 5 so stored procedures shouldn't be a problem. The only problem is that I don't know whether the application that I use which requires this query is capable of calling a Stored procedure instead of a query, so therefore I rather use a view/query.

could you explain in words what the "application that I use which requires this query" expects to see

what is that stuff with the variable and the mod function and all that?

If you are using a .NET application I can tell from experience that calling a stored procedure is not a problem. Unless you are using some other type of application, in which case I would have to ask what it is.