Google Messages fails to register with the RCS servers on some Samsung Galaxy handsets after the user migrates to a new device or ports their number to a new carrier. The app either stays stuck on "Setting up" or reports status code 3100, described in the app as "Trouble connecting. Awaiting retry", and conversations silently fall back to plain SMS/MMS — losing typing indicators, read receipts, high-quality media and end-to-end encryption.
Google has attributed the failure to corrupted cache files carried over by Samsung's Smart Switch migration tool, which leave the Carrier Services component unable to verify the phone number. The troubleshooting procedure Google published works only intermittently, and a number of affected users report that a full factory reset — set up as a new device, without Smart Switch — was the only reliable recovery.
Reports concentrate on Galaxy Z Fold 6 and Galaxy Z Fold 8 owners, though the trigger appears to be the migration itself rather than any specific model. This is not a widespread outage: unaffected devices continue to use RCS normally.
Steps to reproduce:
- Use Samsung Smart Switch to transfer data from an existing phone to a new Galaxy device (or port the number to a different carrier).
- Open Google Messages on the new device and enable RCS chats.
- RCS registration never completes — the setting remains on "Setting up", or the RCS status screen shows code 3100 — and outgoing messages are sent as SMS instead.
Solution: Not yet available. Google has acknowledged the problem and published troubleshooting steps, but no patched version of Google Messages or Carrier Services has been released.
Workaround: Google's recommended sequence is to update Google Messages to the latest version, toggle RCS off, clear the storage/data of the Carrier Services app, restart the phone, then toggle RCS back on; results are inconsistent. Some users report success only after waiting roughly 48 hours following the cache clear before re-enabling RCS. The most reliable recovery reported is a factory reset with the device set up fresh, transferring data manually rather than through Smart Switch. To avoid the problem when changing networks, disable RCS on the old device before the port and re-enable it only once the carrier confirms the port has completed.
Severity: Major (breaks a core messaging feature outright for affected users, with no vendor fix and only unreliable workarounds — the most dependable recovery is a factory reset, which costs the user their local data — but the impact is limited to a subset of Galaxy owners who have just migrated, and there is no security exposure)
First seen: August 2026
Affected product: Google Messages
Affected platforms: Android — reported on Samsung Galaxy devices, notably the Galaxy Z Fold 6 and Galaxy Z Fold 8, following a Samsung Smart Switch migration or a carrier number port
Affected versions: Unknown — no source identifies specific Google Messages or Carrier Services build numbers
Fixed versions: Not yet available
Links:
- https://9to5google.com/2026/08/19/google-messages-rcs-3100-error/ (19 August 2026)
- https://www.androidauthority.com/google-messages-rcs-connection-bug-3700507/ (19 August 2026)
- https://mobilesyrup.com/2026/08/19/google-messages-rcs-broken-some-users/ (19 August 2026)
- https://www.androidpolice.com/google-messages-rcs-is-broken-on-some-phones/ (19 August 2026)
- https://sammyguru.com/samsung-smart-switch-breaking-google-messages-rcs/ (19 August 2026)
- https://www.androidcentral.com/apps-software/google-messages-rcs-is-breaking-for-some-galaxy-users-after-using-smart-switch (19 August 2026)
- https://www.phonearena.com/news/some-galaxy-users-having-issues-with-rcs-messages_id156417 (date unknown)