Question: I am developing an outlook add-in, i have a form with a button which has a "Close.png" icon the Imagesource of the button is 

```
<Button.Background>
            <ImageBrush ImageSource="pack://siteoforigin:,,,/Resources/Close.png"/>
            </Button.Background>

```

, when i deploy the solution using clickonce and after install it successfully and when i tried to run it from outlook y got the following exception message: "\Addin.Outlook\Addin.Outlook\publish\Resources\Close.png", having Content as build action and copy always as copy to output directory.
I need some help, cheers.

Answer: 
A regex-way to validate this range:

```
\b(?:4[0-9]{2}|5[0-4][0-9]|550)\b

```

See [demo](https://regex101.com/r/uH9lT8/3). It will also work in larger texts since `\b` boundaries are used. In case of whole strings, use `^` and `$` around instead of `\b`.
Try `/(([4][0-9]{2,2})|([5][0-4][0-9])|(550))/`
(I haven't tested it). I dont know if there is an easier way.