---
title: "Amplia Reg command: **backfill-holder-normalized-alternative-email**"
description: "Amplia Reg command backfill-holder-normalized-alternative-email: fills in the normalized alternative email of holders registered before version 8.4.0."
canonical: "https://docs.lacunasoftware.com/en-us/articles/amplia-reg/on-premises/tool/backfill-holder-normalized-alternative-email"
locale: "en"
product: "Amplia Reg"
last_updated: "2026-10-13"
---

# Amplia Reg command: **backfill-holder-normalized-alternative-email**

## Name

`backfill-holder-normalized-alternative-email` - Fills in the normalized alternative email of older holders

## Syntax

```sh
dotnet Lacuna.AmpliaRegNg.Site.dll [settings] -- backfill-holder-normalized-alternative-email [options]
```

Or, on Docker:

```sh
docker run -i lacunasoftware/ampliareg:x.y.z [settings] -- backfill-holder-normalized-alternative-email [options]
```

> **Info**
>
> Replace `x.y.z` above with the desired version

The `settings` arguments are additional settings to overwrite settings from configuration files and environment variables,
for instance `--Section1:Name1=value1 --Section2:Name2=value2`.

Options:

* `--batchsize <batch-size>`: number of holders to process per batch. Default: 100
* `--logfrequency <log-frequency>`: how often, in number of processed holders, progress is written to the log. A value less than or equal to zero turns this log off. Default: 5

## Description

Version [8.4.0](https://docs.lacunasoftware.com/en-us/articles/amplia-reg/changelog#8.4.0) started storing, for each holder, a normalized version of the alternative email in addition
to the alternative email as it was entered. This value is filled in automatically whenever a holder's alternative email is saved, but it
is empty for holders registered before that version.

The `backfill-holder-normalized-alternative-email` command goes through every holder that has an alternative email and fills in the
normalized alternative email from the value already registered. The alternative email itself is not changed.

> **Info**
>
> Run this command once, after updating to version 8.4.0 or later. Holders created, or whose alternative email was changed, from that
> version on already have the normalized value filled in, and running the command again does no harm.

Before processing, the command shows how many holders were found and asks for confirmation (`Y`) before proceeding.

## See also

* [Amplia Reg command-line tool](https://docs.lacunasoftware.com/en-us/articles/amplia-reg/on-premises/tool)