SMS Error Codes
Complete reference guide for SMS error codes. Understand what each error means and how to resolve delivery failures with WhatSnap SMS on Android.
When SMS messages fail to send through WhatSnap, you may receive error codes that indicate why the delivery failed. This comprehensive guide explains each error code and provides solutions.
Common Causes of Message Failures
Before diving into specific error codes, these are the most common reasons for message failures:
1. Sending Speed Too Fast
Problem: Sending messages too quickly triggers carrier spam filters or device limits.
Solution:
Use drip mode in your workflows
Limit to 1 message per minute maximum
Follow proper SIM warm-up process
2. Improperly Formatted Phone Numbers
Problem: Phone number format doesn't match recipient country requirements.
Common Issues:
Missing country code
Extra spaces or dashes
Invalid format for country
Solution:
US Format: +1XXXXXXXXXX or just XXXXXXXXXX (10 digits)
International: Always include country code (e.g., +44, +61, +64)
Remove spaces, dashes, parentheses
Verify format in GoHighLevel contact record
3. SIM Card Restrictions
Problem: Carrier has banned or rate-limited your SIM card.
Solution:
Reduce sending volume immediately
Wait 24-48 hours before resuming
Contact carrier to remove blocks
Follow avoiding carrier blocks guide
Try different SIM card or carrier
4. Network Operator Processing
Problem: Different carriers process messages differently.
Solution:
A "Failed" response usually means operator couldn't reach recipient
Try different SIM card or device
Verify recipient's number is active
Check recipient carrier isn't blocking messages
Error Code Reference
NO_SERVICE
What it means: Your device has no cell reception.
Common Causes:
Device is in area with no coverage (basement, rural area, etc.)
Underground or inside building with thick walls
Away from any cell tower
Receiving a call while sending messages (interrupts SMS)
Solutions:
Move device to location with better signal
Check signal bars (should have 2-4 bars minimum)
Restart device to reconnect to network
Wait for call to finish if receiving one
Switch from WiFi-only to mobile data
RADIO_OFF
What it means: Device is in airplane mode or radios are disabled.
Common Causes:
Airplane mode is enabled
All radios turned off (cellular, WiFi, Bluetooth)
Solutions:
Disable airplane mode:
Settings → Network → Airplane mode → OFF
Verify cellular radio is enabled
Check mobile data or cellular is turned on
LIMIT_EXCEEDED
What it means: Phone reached the sending queue limit.
Common Causes:
Too many messages queued to send
Device or carrier limit exceeded
Sending too quickly
Solutions:
Reduce sending speed (increase delay between messages)
Clear queued messages in WhatSnap dashboard
Wait for current queue to process
Implement drip mode (1 msg per minute)
See Failed Messages Guide for queue management
GENERIC_FAILURE
What it means: Something went wrong, but the system can't specify what.
Common Causes:
Various carrier-specific issues (see numbered codes below)
Network problems
SIM card issues
Invalid recipient number
Solutions:
Check if error has a number in brackets (e.g., GENERIC_FAILURE [8])
Look up the specific numbered error below
If no number:
Restart device
Check SIM card is inserted properly
Verify recipient number is valid
Try sending to different number to isolate issue
GENERIC_FAILURE [1]
What it means: Destination number is in valid format but not currently assigned.
Explanation: The phone number exists as a valid format but is not allocated to any subscriber.
Solutions:
Verify the recipient's phone number
Contact recipient to confirm their number is active
Number may have been disconnected or changed
Remove invalid numbers from your contact list
GENERIC_FAILURE [8]
What it means: Your carrier has forbidden mobile originating short messages.
Explanation: Your network operator or service provider has blocked outgoing SMS from your account.
Solutions:
Contact your carrier immediately
Explain: Legitimate business use
Request removal of restriction
Check account status with carrier
Verify SMS feature is enabled on your plan
May need to upgrade to business plan
Consider switching carriers if restriction persists
GENERIC_FAILURE [10]
What it means: Outgoing call barred service applies to SMS for this destination.
Explanation: Outgoing SMS to this specific destination is blocked (possibly international).
Solutions:
Check if recipient is international number
Verify your plan includes international SMS (if applicable)
Contact carrier to enable international SMS
May need to add international SMS add-on to plan
GENERIC_FAILURE [17]
What it means: PLMN (carrier network) failures - network cannot service request.
Explanation: Problems in the carrier's MAP (Mobile Application Part) system.
Solutions:
This is a carrier/network issue, not your fault
Wait 30-60 minutes and retry
Contact carrier support if persists
Try sending to different recipient to confirm issue
May be temporary network maintenance
GENERIC_FAILURE [21]
What it means: Recipient equipment doesn't want to accept the message.
Explanation: Recipient's device or carrier is rejecting the message (not busy or incompatible).
Solutions:
Recipient may have blocked your number
Recipient's device or carrier blocking messages
Try calling recipient to discuss
Message content may be flagged as spam
Ask recipient to check blocked numbers list
GENERIC_FAILURE [27]
What it means: Interface to destination is not functioning correctly.
Explanation: Unable to deliver message to recipient due to technical issues at recipient's end.
Common Causes:
Recipient's phone is off or offline
Recipient's device has technical problems
Physical layer or data link layer failure at recipient
Recipient's phone is out of service
Solutions:
Wait and retry later (recipient's phone may be off)
Try different contact method (call recipient)
Verify recipient number is correct and active
GENERIC_FAILURE [28]
What it means: Subscriber is not registered in the PLMN (carrier network).
Explanation: IMSI (International Mobile Subscriber Identity) is not known by the network.
Solutions:
Recipient's SIM card may not be registered
Recipient may need to contact their carrier
Number may be newly activated (wait 24 hours)
Verify number is correct
GENERIC_FAILURE [29]
What it means: Requested facility is not supported by the carrier network.
Explanation: The PLMN doesn't support the SMS facility you're requesting.
Solutions:
May be trying to send to carrier that doesn't support SMS
Check if sending to international number with incompatible carrier
Verify recipient carrier supports SMS
Try different messaging method (WhatsApp)
GENERIC_FAILURE [30]
What it means: Subscriber is not registered in the HLR (Home Location Register).
Explanation: IMSI or directory number is not allocated to a subscriber.
Solutions:
Number doesn't exist or isn't active
Verify recipient's phone number
Number may have been disconnected
Ask recipient to confirm their number
GENERIC_FAILURE [38]
What it means: Network not functioning correctly - long-term problem.
Explanation: Network malfunction likely to last a long time; retrying immediately won't help.
Solutions:
Wait several hours before retrying
This is a carrier network issue
Contact carrier support to report network problems
Use alternative messaging method in meantime
Check carrier's service status page
GENERIC_FAILURE [41]
What it means: Network not functioning correctly - temporary problem.
Explanation: Network malfunction that won't last long; retry soon.
Solutions:
Wait 5-15 minutes and retry
Temporary network congestion or maintenance
Usually resolves on its own quickly
GENERIC_FAILURE [42]
What it means: High traffic - SMS service cannot be provided.
Explanation: Network congestion due to high message volume.
Solutions:
Wait 15-30 minutes and retry
Common during peak hours or emergencies
Try sending during off-peak hours
This is carrier overload, not your fault
GENERIC_FAILURE [47]
What it means: Resources unavailable.
Explanation: Network resources temporarily unavailable.
Solutions:
Wait and retry in a few minutes
Network may be under heavy load
Try again during off-peak hours
GENERIC_FAILURE [50]
What it means: User hasn't completed necessary administrative arrangements.
Explanation: Your account or the recipient's account needs administrative setup.
Solutions:
Check your account is fully activated with carrier
Verify SMS is enabled on your plan
May need to contact carrier to enable SMS features
Recipient may need to activate their SMS service
GENERIC_FAILURE [69]
What it means: Network unable to provide requested SMS service.
Explanation: Network can't provide the specific SMS service requested.
Solutions:
Carrier doesn't support this type of SMS
Try plain text (no special characters)
Reduce message length
Verify carrier supports SMS to this destination
GENERIC_FAILURE [81]
What it means: Message reference not currently in use.
Explanation: The message reference number is invalid on the network interface.
Solutions:
This is usually a temporary error
Retry sending the message
Restart WhatSnap Gateway app
May resolve itself automatically
GENERIC_FAILURE [95]
What it means: Invalid message event (general).
Explanation: Message format or content is invalid.
Solutions:
Check message doesn't contain unsupported characters
Reduce message length (keep under 160 characters)
Remove emojis or special symbols
Use plain text only
GENERIC_FAILURE [96]
What it means: Mandatory information element is missing or has content error.
Explanation: Required message data is missing or incorrect.
Solutions:
Verify phone number format is correct
Check message content is valid
Restart WhatSnap Gateway app
Re-send message with simpler content
GENERIC_FAILURE [97]
What it means: Message type not recognized.
Explanation: Equipment doesn't recognize this message type or it's not implemented.
Solutions:
Try sending plain text instead of MMS
Remove attachments and send text only
Ensure not trying to send unsupported message type
GENERIC_FAILURE [98]
What it means: Message not compatible with short message protocol state.
Solutions:
Restart WhatSnap Gateway app
Wait a few minutes and retry
May be temporary protocol sync issue
GENERIC_FAILURE [99]
What it means: Information elements not recognized in message.
Explanation: Message contains unrecognized elements (not required for processing, but present).
Solutions:
Simplify message content
Remove special formatting
Use plain text only
GENERIC_FAILURE [111]
What it means: Protocol error (general).
Explanation: Network protocol error occurred.
Solutions:
Wait and retry
Restart device
Restart WhatSnap Gateway app
Contact support if persists
GENERIC_FAILURE [127]
What it means: Interworking with network that doesn't provide causes.
Explanation: Connected to network that doesn't give error details.
Solutions:
Can't determine exact cause
Try general troubleshooting:
Verify number is correct
Check network connection
Restart device
Retry later
GENERIC_FAILURE [128-145]
Message Type and Coding Errors:
128
Telematic interworking not supported
Use standard SMS only
129
Short message type 0 not supported
Don't use type 0 messages
130
Cannot replace short message
Send new message instead
143
Unspecified TP-PID error
Simplify message
144
Data coding scheme not supported
Use standard text encoding
145
Message class not supported
Use default message class
159
Unspecified TP-DCS error
Use plain text
General Solutions:
Send plain text messages
Remove special formatting
Don't use advanced SMS features
Keep messages simple
GENERIC_FAILURE [160-161]
Command Errors:
160
Command cannot be actioned
161
Command unsupported
Solutions:
Don't use SMS commands
Send regular text messages only
GENERIC_FAILURE [176-199]
Service Center and Message Errors:
192
SC (Service Center) busy
Wait and retry
193
No SC subscription
Contact carrier to enable SMS
194
SC system failure
Wait for carrier to fix
195
Invalid SME address
Check recipient number format
196
Destination SME barred
Recipient blocked messages
197
Duplicate message rejected
Don't send same message twice quickly
GENERIC_FAILURE [208-213]
SIM Card Storage Errors:
208
SIM SMS storage full
Delete messages from SIM
209
No SMS storage capability in SIM
Use device storage, not SIM
210
Error in MS (Mobile Station)
Restart device
211
Memory capacity exceeded
Clear message storage
212
SIM application toolkit busy
Wait and retry
213
SIM data download error
Restart device or contact carrier
Solutions:
Clear old messages from phone and SIM
Settings → Apps → Messages → Storage → Clear cache
Delete unnecessary message threads
Restart device
GENERIC_FAILURE [300-322]
Device and SIM Errors:
300
ME (Mobile Equipment) failure
Restart device
301
SMS service reserved
Wait and retry
302
Operation not allowed
Check permissions
303
Operation not supported
Don't use this feature
310
SIM not inserted
Insert SIM card
311
SIM PIN required
Enter SIM PIN
313
SIM failure
Restart device or replace SIM
314
SIM busy
Wait and retry
315
SIM wrong
Use correct SIM
316
SIM PUK required
Contact carrier for PUK code
321
Invalid memory index
Clear message storage
322
Memory full
Delete old messages
GENERIC_FAILURE [330-332]
Network Service Errors:
330
SMSC address unknown
Contact carrier to configure
331
No network service
Check signal/move to coverage area
332
Network timeout
Wait and retry
GENERIC_FAILURE [500-522]
Application-Level Errors:
500
Unknown error
Restart app and retry
512
User abort
Message was cancelled
513
Unable to store
Clear device storage
514
Invalid status
Restart app
515
Device busy or invalid character
Wait or simplify message
516
Invalid length
Shorten message
517
Invalid character in PDU
Remove special characters
518
Invalid parameter
Check message format
521
Timer expired
Retry sending
522
Operation temporarily not allowed
Wait and retry
GENERIC_FAILURE [532-538]
SIM and Protocol Errors:
532
SIM not ready
Wait 1-2 minutes, retry
534
Cell broadcast error
Ignore if not using CB
535
Protocol stack busy
Wait and retry
538
Invalid parameter
Check number format
UNKNOWN_ERROR [*]
What it means: Something went wrong with no details available.
Solutions:
Restart WhatSnap Gateway app
Restart Android device
Check internet connection
Verify SIM card is working (test native SMS)
Check for device updates
Contact support if persists
Error Code 503
What it means: Error from GoHighLevel - Custom provider not selected.
Explanation: User hasn't selected WhatSnap as the custom SMS provider in GoHighLevel.
Solutions:
Interpreting Error Patterns
High Failure Rate Across Multiple Contacts
If many messages fail:
Problem is likely with your device or carrier
Check your SIM card status
Verify you're not blocked by carrier
Reduce sending speed significantly
Follow SIM warm-up process
Failures to Specific Numbers Only
If only certain numbers fail:
Problem is likely with recipient
Verify phone numbers are correct format
Check recipients' phones are active
Numbers may be disconnected
Recipients may have blocked you
Intermittent Failures
If failures are random:
Check network signal strength
Verify device isn't entering sleep mode
Check battery optimization settings
May be carrier congestion (retry during off-peak)
All Messages Failing Suddenly
If everything stops working:
Check WhatSnap Gateway app is running
Verify device has internet connection
Check SIM card hasn't been blocked
Test sending SMS directly from phone
Reconnect WhatSnap integration
Getting Help with Errors
When contacting support about errors:
Include this information:
Contact: support@whatsnap.ai
Related Resources
Database Reactivations - Avoiding Blocks
Error codes based on GSM standards and carrier implementations. Specific meanings may vary slightly by carrier and device.
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