Updated on Sep 14, 2026
Full error name: “Error 404: The login failed, what should I do?“
Possible causes
Wrong URL at login
The most likely reason is though that you logged in to your WooCommerce inside Nembol using the wrong URL.
Server connection failure
Sometimes, the connection between Nembol and WooCommerce fails because there are block functions active on your WooCommerce website, or server instance, which reject the connection with Nembol or other third-party apps.
How to solve a wrong URL issue
The URL required by Nembol is the complete URL, complete with http:// or https://, and with or without the “www.” part of the domain, exactly as configured in your WooCommerce. Anything less or different, even if initially may grant you access, may create issues in the Sync. See the screenshot below.
Please note that if you successfully complete a login using an incomplete URL, you are likely to have subsequent issues with the connection of your WooCommerce webhooks, which will slow down stock sync and possibly other functions.
How to solve a potential server connection failure
If your hosting provider or security plugin is blocking Nembol, whitelist Nembol before disabling any firewall or security plugin.
Please provide your hosting provider or security service with the following information:
Nembol outgoing IP:
136.243.53.123Nembol User-Agent for product image downloads:
Mozilla/5.0 (compatible; Nembol/1.0; +https://www.nembol.com)User-Agent for WooCommerce API requests:
WooCommerce REST API - JS ClientAsk your hosting provider or security plugin to allow requests from Nembol using the information above.
Common symptoms of a blocked connection
A server or security service blocking Nembol may cause symptoms such as:
- The WooCommerce channel suddenly appearing disconnected after working correctly for some time.
- Products being imported without their images.
- Login or connection attempts failing unexpectedly.
- Requests returning errors such as
401,403, or999.
If the problem persists
If you are still unable to connect WooCommerce to Nembol after checking the URL and whitelisting Nembol, contact your hosting provider and ask them to check whether requests from Nembol are being blocked by their firewall or security system.
Provide them with the Nembol IP address and User-Agent above and ask them to whitelist Nembol.
Once the changes have been made, retry the WooCommerce connection process in Nembol.