Why did my 4S eSIM fail to install?

Short answer: installation can fail because the code was already used, the phone is not ready to add an eSIM, or the phone cannot reach the eSIM download server. Do not delete any profile that may already be installed.

Common error types

• Code Invalid / Invalid activation code: the eSIM may already be installed, or the code was already used.
• Unable to add eSIM: check device compatibility, carrier lock status, iOS/Android updates, and your internet connection.
• eSIM already in use: the profile may already be installed on this phone or another device.
• Download or server error: the phone may not be able to reach the SM-DP+ server from the current network.

If the error mentions an invalid code

Before trying to install again, check whether the eSIM is already on the phone. If the ICCID on your phone matches the ICCID on your 4S eSIM installation page, the eSIM is already installed and the code should not be scanned again.

Confirm the installed eSIM by ICCID

The most reliable way to identify your 4S eSIM is to compare the ICCID. The ICCID is usually a 20-digit number that starts with 89.

1. Open your 4S eSIM installation page or 4S service page and find the ICCID shown for your purchased eSIM.
2. On your phone, find the installed eSIM ICCID.
3. Compare the ICCID on your phone with the ICCID on your 4S page. You can compare the full number or the last 6 digits.

iPhone

Go to Settings > General > About, then scroll down to the eSIM / SIM section and look for ICCID. If the ICCID matches the ICCID on your 4S page, that eSIM is already installed on your iPhone.

Samsung

Go to Settings > Connections > SIM manager, select the eSIM line, then open More information if available. Look for ICCID.

Google Pixel and other Android phones

Try Settings > Network & internet > SIMs to find the eSIM line. Then check Settings > About phone > SIM status or SIM status (SIM slot 1 / SIM slot 2) and look for ICCID.

Check RSP / SM-DP+ connectivity

If installation fails with a download or server-related error, test whether your current phone network can reach the RSP / SM-DP+ service. This check uses a public connectivity test address and does not reveal the actual SM-DP+ server used by your 4S eSIM.

1. On the same phone and the same internet connection, open a browser.
2. Go to https://smdp.io/.
3. If you see an SSL, certificate, or privacy warning, the connection is usually reaching the RSP / SM-DP+ service correctly. Go back to eSIM installation and try again.
4. If you see 403, Forbidden, Access denied, no response, a timeout, or a DNS error, your current ISP, Wi-Fi, VPN, firewall, Private DNS, or security app may be blocking the connection.
5. If the test looks blocked, switch networks and try again. For example, use another Wi-Fi provider, mobile data from another SIM, a mobile hotspot, or turn off VPN/Private DNS temporarily.

Before trying again

1. Restart your phone.
2. Make sure the phone has a stable internet connection.
3. Turn off VPN, Private DNS, ad blockers, or security filters temporarily.
4. Check that the phone supports eSIM and is not carrier-locked.
5. Check whether the ICCID is already installed on your phone.
6. Try One-Click Install again, or use manual installation with the QR code or activation details from your 4S service page.

What to send support

• The full error text.
• A screenshot of the error.
• Your phone model and purchase region.
• Your ICCID if available.
• A screenshot of your SIM/eSIM list if the eSIM may already be installed.
• What happened when you opened https://smdp.io/: SSL/certificate warning, 403/Forbidden, timeout, DNS error, or no response.

Need help?

Contact 4S support through support@4s.net, a Zendesk support ticket, or Zendesk live chat. Do not reply to hi@4s.net; it is an automatic order and installation email sender.