**Before attempting either an in-place upgrade or a clean installation, we strongly recommend that users [back up their systems](/doc/backup-restore/).**
Current Qubes R3.2 systems cannot be upgraded in-place to R4.0.
A full backup, clean 4.0 install, and restore is required.
This can be done by following the procedure below.
2. If this is your only computer, and you do not have a R3.2 installer, you should also create a separate R3.2 USB drive or DVD installer at this time.
3. Follow the **Creating a Backup** section in the [Backup, Restoration, and Migration](/doc/backup-restore/) guide to back up **all VMs** except sys-usb.
6. Verify the integrity of your backup by following the **Restoring from a Backup** section in the [Backup, Restoration, and Migration](/doc/backup-restore/) guide and:
Go back and repeat the backup steps, review the documentation or search the qubes-users mailing list, or ask for assistance on the [qubes-users mailing list](/support/#qubes-users) or IRC.
2. Since patches may have been released since your installation image was created, update Qubes R4.0 by going to the dom0 command line (**Qubes menu -> Terminal Emulator**) then running:
We recommend that you restore only your [TemplateBasedVMs](/doc/glossary/#templatebasedvm) and [StandaloneVMs](/doc/glossary/#standalonevm) from R3.2.
Using [TemplateVMs](/doc/templates/) and [SystemVMs](/doc/glossary/#systemvm) from R3.2 is not fully supported (see [#3514](https://github.com/QubesOS/qubes-issues/issues/3514)).
Instead, we recommend using the TemplateVMs that were created specifically for R4.0, which you can [customize](/doc/software-update-vm/) according to your needs.
For the TemplateVM OS versions supported in R4.0, see [Supported Versions](/doc/supported-versions/#templatevms).
If the restore tool complains about missing templates, you can select the option to restore the AppVMs anyway, then change them afterward to use one of the default R4.0 templates.
One of differences between R3.2 and R4.0 is the handling of DisposableVMs.
In R3.2, a DisposableVM inherited its network settings (NetVM and firewall rules) from the calling qube.
In R4.0, this is no longer the case.
Instead, in R4.0 it's possible to create multiple DVM Templates and choose which one should be used by each qube.
It's even possible to use different DVM Templates for different operations from the same qube.
This allows much more flexibility, since it allows you to differentiate not only network settings, but all of a qube's properties (including its template, memory settings, etc.).
Restoring a backup from R3.2 preserves the old behavior by creating separate DVM Template for each network-providing qube (and also `disp-no-netvm` for network-isolated qubes).
Then, each restored qube is configured to use the appropriate DVM Template according to its `netvm` or `dispvm_netvm` property from R3.2.
This way, DisposableVMs started on R4.0 by qubes restored from a R3.2 backup have the same NetVM settings as they had on R3.2.
If you find this behavior undesirable and want to configure it differently, you can remove those `disp-*` DVM Templates.
But, to do so, you must first make sure they are not set as the value for the `default_dispvm` property on any other qube.
Both Qubes Manager and the `qvm-remove` tool will show you where a DVM Template is being used, so you can go there and change the setting.
We strongly recommend that you update **all** TemplateVMs and StandaloneVMs before use so that you have the latest security patches from upstream distributions.
In addition, if the default templates have reached EOL (end-of-life) by the time you install R4.0, we strongly recommend that you upgrade them before use.
Please see [Supported Versions](/doc/supported-versions/) for information on supported OS versions and consult the guides below for specific upgrade instructions:
