> For the complete documentation index, see [llms.txt](https://docs.mikopbx.com/mikopbx/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mikopbx.com/mikopbx/english/faq/outbound-routing/remove-all-special-characters-from-the-dialed-number.md).

# Remove all special characters from the dialed number

Some softphones / CTI solutions transmit a phone number with special characters when dialing, for example **+371(2) 229-3042**

Such a call is very likely to fail, it will be completed by mistake.

1. To solve the problem of "filtering" characters, an additional context should be described through the [Customization of system files](/mikopbx/english/manual/system/custom-files.md) menu

<figure><img src="/files/tYsBgqXvD9DV5euOc4N0" alt=""><figcaption><p>System file customization menu</p></figcaption></figure>

2. We will edit the **extensions.conf** file.

<figure><img src="/files/R61HVwQh4xX75UmmNNdE" alt=""><figcaption></figcaption></figure>

3. Add the following context to the end of the file:

```php
[all_peers-custom]

exten => s,1,NoOp(Cleaning dst number)
	same => n,Set(cleanNumber=${FILTER(\*\#1234567890,${EXTEN})})
	same => n,ExecIf($["${EXTEN}" != "${cleanNumber}"]?Goto(all_peers,${cleanNumber},1))
	same => n,return
```

<figure><img src="/files/cddcaqszxC9gl7i6HTe3" alt=""><figcaption></figcaption></figure>

{% hint style="success" %}
According to the described rule, only the characters \*#1234567890 will remain in the dialed number
{% endhint %}


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