Home Assistant not working after an update: what to check and how to recover

Home Assistant updates normally complete without trouble. Occasionally, however, the dashboard no longer opens after a restart, integrations become unavailable, automations stop responding, or the system repeatedly restarts.

A fault noticed after an update does not necessarily mean the whole installation is damaged. The safest approach is to define the scope, preserve useful evidence, and only then choose a recovery step.

• The dashboard does not open at all: the cause may be Home Assistant, its host, a virtual machine, a container, the network, or simply the address used to connect.
• The dashboard opens, but integrations or entities are unavailable: this is usually not a complete controller failure. Start with the affected integration and its messages.
• Automations do not run: confirm that they are enabled, their triggers and conditions receive data, and their traces show an attempted run.
• Errors or restarts appear: note their time and frequency. A repeating pattern can separate a Core issue from a host or storage problem.
• Only one app or custom component fails: investigate that component separately before rolling back the entire system.

If the symptom is a single unavailable state, the guide to an unavailable Home Assistant entity provides a more focused checklist.

Timing alone does not prove causation. At the same moment, a device may have received a new IP address, a cloud token may have expired, storage may have failed, or the router may have developed a fault.

Establish whether the update affected Home Assistant Core, Home Assistant OS, Supervisor, an app, a vendor integration, or a HACS component. Record the version before and after, the approximate time, and the first visible symptom. Check the release notes and backward-incompatible changes for the component that changed.

If several items were updated together, do not guess which one caused the fault. Compare the update times with the logs and the earliest error first.

• Confirm that the host is powered on and visible in the router or virtual machine console.
• Try the local IP address or the correct hostname. Failed remote access does not prove that Home Assistant has stopped locally.
• If the interface is available, review Settings → System → Logs and Repairs. The first startup error is often more useful than dozens of later consequences.
• Check system information and free space. A full disk can prevent database writes, updates, and normal service startup.
• On Home Assistant OS, the console and CLI can show Core, Supervisor, and host status and logs. With Docker or a virtual machine, inspect the equivalent layers with the platform's own tools.

Avoid repeated restarts before recording the messages. Restarting can remove the clearest view of when the failure began.

Recovery mode appears when Home Assistant detects a configuration problem and loads a minimal set of integrations so that the configuration can be repaired. Its presence points towards configuration or loading errors.

Safe mode runs Home Assistant Core without custom integrations, custom cards, or themes. If the fault disappears in Safe mode, the cause lies outside Core itself and is often a HACS or other custom element.

Safe mode is a diagnostic tool, not a repair by itself. Preserve the logs and identify the responsible component before disabling or deleting anything.

• Integrations: check configuration status, reauthentication prompts, Repairs, and the integration-specific log messages.
• Entities: compare whether one entity, one device, or every device in the integration is unavailable.
• Automations: review traces, triggers, conditions, and dependent entities. An update may expose an older mistake or a changed action.
• Apps: separate the app's state from Home Assistant Core and inspect its own log.
• HACS and custom components: verify compatibility and the maintainer's known issues. Do not update several components at once while troubleshooting.

One broken integration rarely justifies restoring the whole installation. The guides to Home Assistant integrations and automations add useful context.

If the dashboard is unreachable, Core will not start, or the host keeps rebooting, inspect the installation layer. On Home Assistant OS this includes the system and storage; with Docker it also includes the container, volumes, and engine logs; in a virtual machine it includes allocated resources, the virtual disk, and the hypervisor console.

A sudden loss of many integrations can come from a network, DNS, USB, or storage issue. For PC and mini PC installations, knowing the installation method and data location matters; the guide to Home Assistant on a PC, mini PC, or laptop explains that foundation.

If you see input/output errors, file-system damage, or unstable hardware, further restarts and updates can make recovery harder. Secure any accessible data first.

A recent backup can recover configuration and selected data, but restoring it overwrites the chosen parts of the current system. It can therefore roll back automations, devices, history, and other changes made after the backup.

Before restoring, verify the date, contents, storage location, and access to the encryption key. If the system still runs partially, preserve the current logs and configuration. Then decide whether a full restore, a partial restore, or a targeted repair is the safer option.

The Home Assistant backup and restore guide explains preparation and recovery in more detail.

• Do not randomly delete configuration files, databases, or component folders.
• Do not remove and re-add several integrations at once.
• Do not install more updates merely to see whether the fault disappears.
• Do not restore an old backup without checking what it will overwrite.
• Do not reset the whole installation before knowing whether the issue affects Core, the host, the network, or one app.
• Do not publish complete logs before checking them for addresses, tokens, and other private data.

Good troubleshooting changes one thing at a time and checks the result after each step. That makes it possible to know what actually helped.

• Home Assistant will not start or is caught in a restart loop.
• The logs show migration, database, file-system, or input/output errors.
• The system only starts in Recovery mode or Safe mode, but the cause remains unclear.
• Several unrelated integrations fail at the same time.
• The issue may involve Docker, a virtual machine, Home Assistant OS, storage, or hardware.
• You are unsure whether the backup is complete or which data a restore will roll back.

At this point, trial-and-error changes can make the configuration harder to recover. Stop making changes, preserve the logs, and note the versions and steps already tried.

I can help remotely identify the cause and choose the safest way to bring the system back into operation.

• Home Assistant: Recovery mode and Safe mode
• Home Assistant: Repairs dashboard
• Home Assistant: backup and restore
• Home Assistant OS: logs, CLI, and updates