# Unable to make MC7455 recognize my SIM card

**URL:** <https://forum.sierrawireless.com/t/unable-to-make-mc7455-recognize-my-sim-card/34274>\
**Category:** MC/EM Series\
**Created:** [January 8, 2025, 1:15pm UTC](https://forum.sierrawireless.com/t/unable-to-make-mc7455-recognize-my-sim-card/34274 "2025-01-08T13:15:41Z")\
**Posts on this page:** 1\
**Showing post:** 4

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**Author:** ![jyijyi](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.sierrawireless.com/jyijyi/32/4766_2.png) [@jyijyi](https://forum.sierrawireless.com/u/jyijyi)\
**Post date:** [January 8, 2025, 2:18pm UTC](https://forum.sierrawireless.com/t/unable-to-make-mc7455-recognize-my-sim-card/34274/4 "2025-01-08T14:18:51Z")

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In windows, you can run the exe file to update

In linux, are you sure /dev/ttyUSB2 is the DM port?

> [@EM7455 can't connect to T-Mobile (+CME ERROR: no network service)](https://forum.sierrawireless.com/t/em7455-cant-connect-to-t-mobile-cme-error-no-network-service/22928):
>
> I have a rebranded (Dell) EM7455 that works great on AT&T but I can’t get it to connect to T-Mobile. When I try AT!SCACT=1,1 it returns +CME ERROR: no network service I know my SIM is active because I can put it in a microtik router and everything works fine. What I have tried: 1a. Flashing the modem with the Generic firmware package: sudo qmi-firmware-update -t /dev/ttyUSB0 --update-qdl SWI9X30C\_02.33.03.00.cwe SWI9X30C\_02.33.03.00\_GENERIC\_002.072\_000.nvu sudo qmi-firmware-update -t /dev/tt…

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