google-gemini/gemini-cli · error · Error

Extension "${previousName}" was not already installed, canno

Error message

Extension "${previousName}" was not already installed, cannot update it.

What it means

Thrown on the update path (`previousExtensionConfig` was supplied, so `isUpdate` is true) when no currently-loaded extension matches `previousName`. The update logic needs the previous extension's hooks/skills/enablement state to migrate cleanly, so a missing previous extension is fatal.

Source

Thrown at packages/cli/src/config/extension-manager.ts:310

        throw new Error(`Unsupported install type: ${installMetadata.type}`);
      }

      try {
        newExtensionConfig = await this.loadExtensionConfig(localSourcePath);

        const newExtensionName = newExtensionConfig.name;
        const previousName = previousExtensionConfig?.name ?? newExtensionName;
        const previous = this.getExtensions().find(
          (installed) => installed.name === previousName,
        );
        const nameConflict = this.getExtensions().find(
          (installed) =>
            installed.name === newExtensionName &&
            installed.name !== previousName,
        );

        if (isUpdate && !previous) {
          throw new Error(
            `Extension "${previousName}" was not already installed, cannot update it.`,
          );
        } else if (!isUpdate && previous) {
          throw new Error(
            `Extension "${newExtensionName}" is already installed. Please uninstall it first.`,
          );
        } else if (isUpdate && nameConflict) {
          throw new Error(
            `Cannot update to "${newExtensionName}" because an extension with that name is already installed.`,
          );
        }

        const newHasHooks = fs.existsSync(
          path.join(localSourcePath, 'hooks', 'hooks.json'),
        );
        const previousHasHooks = !!(
          isUpdate &&
          previous &&

View on GitHub (pinned to 5024443c72)

Solutions

Uninstall the dangling config entry first, then install fresh instead of updating.
Reinstall the previous version so the extension is loadable, then retry the update.
Inspect `~/.gemini/extensions/` and remove stale entries before retrying.

Example fix

// before
installOrUpdateExtension(meta, previousConfig)  // previous no longer on disk
// after
await uninstallExtension(previousName); await installOrUpdateExtension(meta)

Defensive patterns

Strategy: validation

Validate before calling

const previous = extensionManager.getExtensions().find((e) => e.name === previousName);
if (isUpdate && !previous) {
  throw new Error(`Cannot update ${previousName}: not installed.`);
}

Type guard

function isInstalled(name: string, installed: { name: string }[]): boolean {
  return installed.some((e) => e.name === name);
}

Prevention

Before calling update, confirm the previous extension loads via `getExtensions()`.
If a directory was deleted manually, run uninstall first to clean the config.
Don't rely on stale `previousExtensionConfig` after a manual cleanup.

When it happens

Trigger: The previous extension's directory was manually deleted from disk while its config entry persisted; `loadExtensions` skipped it due to a load error; the extension was renamed on disk but the config still references the old name.

Common situations: Manual `rm -rf` of an extension directory; a failed uninstall that left config behind; switching machines with a partial sync; corrupted extension state.

Related errors

AI-assisted analysis of google-gemini/gemini-cli@5024443c72 (2026-08-12). Data as JSON: /api/errors/534f5de6cdda337b. Report an issue: GitHub.