Anyone know this error about install the ERPNext app in the existing site

Installing erpnext…
An error occurred while installing erpnext: ERPNext can only be installed on a fresh site where the setup wizard is not completed.
You can reinstall this site (after saving your data) using: bench --site [sitename] reinstall
Traceback (most recent call last):
File “apps/frappe/frappe/commands/site.py”, line 413, in install_app
_install_app(app, verbose=context.verbose, force=force)
File “apps/frappe/frappe/installer.py”, line 283, in install_app
out = frappe.get_attr(before_install)()
File “apps/erpnext/erpnext/setup/install.py”, line 41, in check_setup_wizard_not_completed
frappe.throw(message) # nosemgrep
File “apps/frappe/frappe/init.py”, line 522, in throw
msgprint(
File “apps/frappe/frappe/init.py”, line 490, in msgprint
_raise_exception()
File “apps/frappe/frappe/init.py”, line 442, in _raise_exception
raise raise_exception(msg)
frappe.exceptions.ValidationError: ERPNext can only be installed on a fresh site where the setup wizard is not completed.
You can reinstall this site (after saving your data) using: bench --site [sitename] reinstall

“how can i resolve this error anyone suggest me another way to install it???”

You cannot install erpnext on a site which is already in use. Create a fresh site, do not use or login to the fresh site. Install erpnext on this fresh site.

First reinstall the site

bench --site sitename reinstall

then install erpnxt

bench --site sitename install-app erpnext

then open your site and complete setup wizards

but i don’t want to lose previous data and in the reinstall process probably we lose the data so is there any another option???

Method 1: Manual Setup (Not Recommended / Risky)

You can bypass the setup wizard by commenting out the setup wizard logic in the codebase. After installing ERPNext, manually create essential records such as:

  • Company
  • Fiscal Year
  • Other mandatory records (e.g. Chart of Accounts, Users)

:warning: Warning: This method is not recommended. It may lead to issues later as ERPNext assumes certain records exist after setup. Use this only if you really know what you’re doing.

Method 2: Backup, Reinstall & Restore (Recommended)

This is the safer and more robust method.

  1. Take a backup of your existing site:
  2. Note down the encryption key
  3. Reinstall current site, install erpnext.
  4. Restore the backup:
    bench --site [sitename] restore --force [path_to_database_backup]
  5. Place the old encryption key back in site_config.json.