+CMS ERROR Codes Explained

This page explains basic terms for radio module enthusiasts and a short list of error codes encountered in modem communication.

What is CMS Error?

+CMS ERROR: <err> indicates an error related to mobile equipment or network.

CMS error codes may occur while sending or receiving SMS messages through a cellular modem. If sending/receiving error happens, the modem will notify with a “+CMS ERROR” along with a numeric code indicating the cause of the error. The CMS error codes are defined in the ETSI GSM specifications (GSM 07.05, GSM 03.40 and GSM 04.11). Below you will find a list of possible CMS errors.


Below you will find a list containing definition of CMS error codes supported by GSM modems.

Error Code Meaning
300 ME failure
301 SMS ME reserved
302 Operation not allowed
303 Operation not supported
304 Invalid PDU mode
305 Invalid text mode
310 SIM not inserted
311 SIM pin necessary
312 PH SIM pin necessary
313 SIM failure
314 SIM busy
315 SIM wrong
316 SIM PUK required
317 SIM PIN2 required
318 SIM PUK2 required
320 Memory failure
321 Invalid memory index
322 Memory full
330 SMSC address unknown
331 No network
332 Network timeout
500 Unknown
512 SIM not ready
513 Message length exceeds
514 Invalid request parameters
515 ME storage failure
517 Invalid service mode
528 More message to send state error
529 MO SMS is not allow
530 GPRS is suspended
531 ME storage full

What is CME Error?

+CME ERROR: <err> indicates an error related to mobile equipment.


Below you will find a list containing definition of CME error codes supported by GSM modems.

Error Description
0 Phone failure
1 No connection to phone
2 Phone adapter link reserved
3 Operation not allowed
4 Operation not supported
5 PH_SIM PIN required
6 PH_FSIM PIN required
7 PH_FSIM PUK required
10 SIM not inserted
11 SIM PIN required
12 SIM PUK required
13 SIM failure
14 SIM busy
15 SIM wrong
16 Incorrect password
17 SIM PIN2 required
18 SIM PUK2 required
20 Memory full
21 Invalid index
22 Not found
23 Memory failure
24 Text string too long
25 Invalid characters in text string
26 Dial string too long
27 Invalid characters in dial string
30 No network service
31 Network timeout
32 Network not allowed, emergency calls only
40 Network personalization PIN required
41 Network personalization PUK required
42 Network subset personalization PIN required
43 Network subset personalization PUK required
44 Service provider personalization PIN required
45 Service provider personalization PUK required
46 Corporate personalization PIN required
47 Corporate personalization PUK required
48 PH-SIM PUK required
100 Unknown error
103 Illegal MS
106 Illegal ME
107 GPRS services not allowed
111 PLMN not allowed
112 Location area not allowed
113 Roaming not allowed in this location area
126 Operation temporary not allowed
132 Service operation not supported
133 Requested service option not subscribed
134 Service option temporary out of order
148 Unspecified GPRS error
149 PDP authentication failure
150 Invalid mobile class
256 Operation temporarily not allowed
257 Call barred
258 Phone is busy
259 User abort
260 Invalid dial string
261 SS not executed
262 SIM Blocked
263 Invalid block
772 SIM powered down

Typical questions regarding CMS Errors:

What is CMS error 350?

CMS Error 350 means that the message was rejected by a cellular operator. Possible reasons:

  • destination phone number is invalid
  • no credits on prepaid SIM card
  • cellular operator has blocked a SIM card

What is CMS error 500?

This error is often caused by the SIM card. Please make sure that it is: activated and have SMS service enabled.

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