ExtendSync may fail to read or write data to NetSuite when all available NetSuite concurrency queues are in use. When this happens, the app will retry several times and notify the user with a message similar to:
“Your NetSuite account is currently busy serving other requests. ExtendSync will attempt the operation a few more times.”
If all retry attempts fail, ExtendSync will show:
“Your NetSuite account was busy serving other requests and prevented us from fetching matching results. Please retry.”
In this situation, the user simply needs to retry the operation.
We also recommend forwarding this article to your NetSuite Admin, as concurrency issues typically require account-level monitoring and optimization.
For NetSuite Admins
NetSuite has a strict concurrency policy and depending on your account concurrency your users may see this error from time to time and will have to retry the operation.
ExtendSync Outlook tries to work around these concurrency limitations with retry logic and attempts to fetch matching NetSuite records. However, there are cases where other integration applications are completely using your queues and in such a case ExtendSync alerts your users and asks them to retry.
How to Diagnose Concurrency Errors
Check the Global Search Script Log
If users experience timeouts or failure to retrieve matching records, you can confirm concurrency issues in the Execution Log:
In NetSuite, go to:
Customization → Scripting → Script DeploymentSearch for:
customdeploy_celigo_global_searchClick Execution Log
Look for this error:
SSS_REQUEST_LIMIT_EXCEEDED
This indicates that ExtendSync’s requests exceeded your account’s concurrency limits
Understanding Your Account Concurrency Limits
You can view your account’s concurrency capacity in NetSuite:
Navigate to:
Setup → Integration → Web Services PreferencesLocate your Account Concurrency Limit
The number listed here is the maximum number of concurrent requests that is allowed for the account.
➡️ Follow this cheat sheet from NetSuite to understand your concurrency limits and usage.
Monitor Integration Usage & Identify Traffic Spikes
NetSuite recommends installing the Application Performance Management (APM) SuiteApp to monitor:
Web Services usage
RESTlet concurrency
Integration load patterns
High-traffic periods
APM provides visibility into which integrations (including non-ExtendSync apps) are consuming your concurrency.
➡️ Learn more about APM SuiteApp
Best Practices to Prevent Concurrency Errors
Review your integration schedule to avoid running heavy API jobs during peak hours.
Use APM or logs to determine which integrations are consuming concurrency.
Set up load balancing or staggering of scheduled scripts.
Ensure roles used by ExtendSync have proper permissions to avoid unnecessary retries.
Work with your admin team to regularly monitor Web Services health.