# Error upgrade from v4.0.1 to v4.2 on LiteSpeed server

**URL:** https://forum.mautic.org/t/error-upgrade-from-v4-0-1-to-v4-2-on-litespeed-server/22904
**Category:** Product Support
**Tags:** mautic-4
**Created:** [March 3, 2022, 2:41pm UTC](https://forum.mautic.org/t/error-upgrade-from-v4-0-1-to-v4-2-on-litespeed-server/22904 "2022-03-03T14:41:38Z")
**Posts on this page:** 1
**Showing post:** 2

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### Author: ![silavapi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/silavapi/32/7424_2.png) [@silavapi](https://forum.mautic.org/u/silavapi)
#### Post date: [March 3, 2022, 2:54pm UTC](https://forum.mautic.org/t/error-upgrade-from-v4-0-1-to-v4-2-on-litespeed-server/22904/2 "2022-03-03T14:54:28Z")

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Hi there!

This sounds like an existing issue.

Please follow the steps outlined in this post:

> [@Error after upgrading to 4.2 clearing cache fails and error: Unknown column last\_built\_date in field list](https://forum.mautic.org/t/error-after-upgrading-to-4-2-from-4-unknown-column-last-built-date-in-field-list/22866/4):
>
> Right - @tobsowo had a similar problem. Other than the usual ‘don’t update in the browser’ message, here’s what helped him: Clear the cache by deleting the cache folder Follow these steps:

If you have further issues please reply over there!

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_[View the full topic](https://forum.mautic.org/t/error-upgrade-from-v4-0-1-to-v4-2-on-litespeed-server/22904)._