---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/45601#article
headline: "45601: Custom Flex UI error"
url: https://www.twilio.com/docs/api/errors/45601
inLanguage: en
dateModified: 2026-03-11T20:01:16.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 45601: Custom Flex UI error

Log Type: APPLICATION

Log Level: ERROR

## Description

Error thrown by a user's custom code/plugin.

### Possible causes

* Custom code has been written to throw and report a Flex error event

### Possible solutions

* Fix custom code so that the error is not thrown
* Remove code which throws and reports a custom Flex error event