> For the complete documentation index, see [llms.txt](https://docs.infotopics.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.infotopics.com/mailscheduler/getting-started/installation-wizard/mailscheduler-installer.md).

# MailScheduler installer

Whether you are upgrading from an older version of MailScheduler, or doing a new installation, the first thing you will see is the install screen:

<figure><img src="/files/uKf9tMFHvTgkXN4zjx0e" alt=""><figcaption></figcaption></figure>

This installer is mostly self-explanatory, but there are differences based on whether this is your first time installing Mailscheduler, whether you are upgrading from a version *before* 5.0.0, or upgrading from a version *after* 5.0.0. Please choose which of the following applies to you, and then follow that installation guide:

{% content-ref url="/pages/A2UW39LRb8eqxuW5BFi7" %}
[New installation](/mailscheduler/getting-started/installation-wizard/mailscheduler-installer/new-installation.md)
{% endcontent-ref %}

{% content-ref url="/pages/tHNyFS7crvGMBGGgiCzt" %}
[Upgrading from a version before 5.0](/mailscheduler/getting-started/installation-wizard/mailscheduler-installer/upgrading-from-a-version-before-5.0.md)
{% endcontent-ref %}

{% content-ref url="/pages/k2VJxDGEwcSPrHCnPScN" %}
[Upgrade from a version after 5.0](/mailscheduler/getting-started/upgrade/upgrade-from-a-version-after-5.0.md)
{% endcontent-ref %}

### Troubleshooting <a href="#troubleshooting" id="troubleshooting"></a>

<details>

<summary>The installer says MailScheduler is installed in a location, but it is no longer installed there</summary>

If this happens, open the registry editor, (Press Windows Key+P, enter regedit, and press enter.) and navigate to:&#x20;

```
Computer\HKEY_CURRENT_USER\Software\infotopics\MailScheduler
```

And remove the saved registry keys here. This can be safely done without any damage to future installations, or your machine.

</details>

<details>

<summary>Error opening file for writing</summary>

<figure><img src="/files/9rY8XJFRnrAg43vD4YrM" alt=""><figcaption></figcaption></figure>

When this error appears, you can simply press the 'Retry' button, and the installation process should continue.&#x20;

If the error message appears again, it is possible that a WriteBackExtreme process is still hanging in the background. In this case, open the Task Manager, and end any remaining processes. Afterwards, the installation should complete correctly.

</details>

<details>

<summary>I accidentally installed MailScheduler as new instead of upgrade.</summary>

When running the Windows installer for the first time, the initial screen gives you the option to perform either a new installation or an upgrade from a version earlier than 5.0.

If you accidentally choose New Installation instead of Upgrade, the installer will proceed with a fresh 5.0 installation. After that, the upgrade option will no longer be available.

Fortunately, this can be resolved.

An uninstall.exe file is included in the folder where the new MailScheduler 6.0 version was installed (typically in C:\Users\\\<username>\AppData\Local\MailScheduler). Run this uninstaller to remove the fresh 6.0 installation. Once it has been removed, run the installer again and select the Upgrade option.

</details>


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