I am using header('Location:') to redirect the user to another webpage. But, instead of overwriting the previous address on the address bar, the new one gets appended to the one already present. For example:

The address bar currently holds:

`localhost/v2/admin`

and there is `header('Location:'.DIRADMIN.'login.php');`
where DIRADMIN is a constant defined as

```
define(DIRADMIN,'localhost/v2/admin/');

```

Then, after the redirect, the new address bar would be

```
localhost/v2/admin/localhost/v2/admin/login.php

```

I thought it was because of the server, I am using. I was using Uniform Server Zero. But then I installed WAMP and the problem continues.

I am still a noob, I have no idea what is causing this and if the problem is because of mod\_rewrite, then on both servers the module was active. I already checked some of the problems like 
[redirect-PHP header(Location:..)](https://stackoverflow.com/questions/7467330/php-headerlocation-force-url-change-in-address-bar)

among others. I even did a google search for this but to no end.
How can I solve this problem?

```
header_remove();

```

will not work as the first address was typed in manually and not set by `header();`