Azure App Service
Azure App Service is a service used to create and deploy scalable, mission-critical web apps.
Fix for error when updating app service confg app settings 'Update web sites config'
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Okoye, Chinelo
10
Reputation points
Hello,
I keep getting this error when trying to update config app settings for my app service. No other updates are being done on the service.
'There was a concurrency conflict. Configuration update for Microsoft.Web.Hosting.Administration.WebCloudProvider failed for maximum number of attempts UpdateSingleSiteConfigurationWithRetry.'
Azure App Service
{count} vote
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Siva Nair 520 Reputation points Microsoft External Staff Moderator2025-08-21T16:48:54.22+00:00 Hi Okoye, Chinelo,
That error happens when multiple configuration updates are attempted at the same time (by portal, ARM, CLI, pipelines, or background processes), and App Service fails after retrying internally.
it might happen-
- Another operation (scale, swap, restart, deployment slot config update, SCM operation, Azure Policy) is updating config at the same time.
- Configuration locks caused by concurrent writes (e.g. portal + automation).
- Transient platform issue while applying settings.
solution steps:
- Retry after a few minutes – usually resolves if it was a transient concurrency lock.
- Make config changes one at a time – avoid updating app settings + connection strings + slot swaps simultaneously.
- Use a single method for update – don’t mix Portal + CLI/ARM at the same time.
- Example (CLI):
az webapp config appsettings set -g <resourceGroup> -n <appName> --settings KEY1=VALUE1
- Example (CLI):
- Stop slot conflicts – if you have deployment slots, check if config is being “swapped” at the same time.
- Check ongoing operations – in Activity Log and Diagnose and solve problems in App Service, see if other config/scale ops are overlapping.
- If stuck (keeps happening for all updates):
- Restart the App Service (forces release of config lock).
- Try updating settings via ARM template/CLI instead of Portal.
- As a last resort: export settings, delete stuck config (via Resource Explorer), then reapply.
refer- https://learn.microsoft.com/en-us/azure/app-service/configure-common?tabs=portal
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Siva Nair 520 Reputation points Microsoft External Staff Moderator
2025-08-25T18:57:26.97+00:00 Hi Okoye, Chinelo,
Just checking in to see if information in comment was helpful. If you have any further concerns or queries, please feel free to post/comment back.
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Goncalo Oliveira 6 Reputation points2025-08-27T11:13:02.74+00:00 This crap just started happening to me today...
Failed to update app settings: There was a concurrency conflict. Configuration update for Microsoft.Web.Hosting.Administration.WebCloudProvider failed for maximum number of attempts UpdateSingleSiteConfigurationWithRetry. Failure details: api-fonixtelematics: There was a concurrency conflict. Configuration update for Microsoft.Web.Hosting.Administration.WebCloudProvider failed for maximum number of attempts UpdateSingleSiteConfigurationWithRetry. Failure details: api-fonixtelematicsRestarting the app doesn't sort it!
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Alex Herčko 5 Reputation points2025-08-27T12:55:57.1433333+00:00 Hi, we have had the exact same issue appear the first time today. Even after retrying multiple times, the issue still persists, and there is no visible operation (e.g. swap) running on the web app slot
There was a concurrency conflict. Configuration update for Microsoft.Web.Hosting.Administration.WebCloudProvider failed for maximum number of attempts UpdateSingleSiteConfigurationWithRetry. Failure details: <app name> -
Okoye, Chinelo 10 Reputation points
2025-08-27T13:15:57.3633333+00:00 The only thing that fixed the issue for me was restarting the function app. None of the other remediation steps worked.
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Goncalo Oliveira 6 Reputation points
2025-08-27T13:18:43.8066667+00:00 Yeah, same... What I ended up doing was forcing a deploy into the RC slot, applying the changes on that same slot (that worked) and then swapping.
After this, I was able to make (other) changes to the production slot, but the issue persisted on the RC slot (which was the previous production slot).
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Paul Upson 0 Reputation points2025-08-27T13:52:04.48+00:00 Wanting to add some more weight to this. Started happening to us from today.
There was a concurrency conflict. Configuration update for Microsoft.Web.Hosting.Administration.WebCloudProvider failed for maximum number of attempts MergeAppSettingsAffecting all deployments to Azure that involve app setting changes. All were working fine yesterday so something has changed.
Having to restart web/function apps is not an option, and neither is re-writing our deployment process to include retries around these config updates.
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Apollogz 1 Reputation point2025-08-27T20:52:30.83+00:00 Same issue for me. Restarting the web app does not fix the issue. I am trying to change one environment variable under the web app/settings.
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Paul Upson 0 Reputation points
2025-08-28T08:45:21.25+00:00 An update for anyone who has a similar use case to us. We are using the
Azure.ResourceManagerNuget package to make these web app settings changes in an custom automated deployment application.The 2 scenarios in which we were experiencing this response, we were not using a retry policy with the ArmClient. We haven't experienced this response when updating web app configuration with a suitable retry policy in place.
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