> 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
System file customization menu
2. We will edit the **extensions.conf** file.
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
```
{% hint style="success" %}
According to the described rule, only the characters \*#1234567890 will remain in the dialed number
{% endhint %}
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