[BUG] DeleteIfExistsAsync throws RequestFailedException with 400 when blob does not exist

[nlriverty]

Library name and version

Azure.Storage.Blobs 12.24.1

Describe the bug

When running this code, the request repeatedly fails:

public async Task DeleteAsync(string url)
    {
        var containerName = _blobStorageSettings.AttachmentsContainerName;
        var blobServiceClient = new BlobServiceClient(_blobStorageSettings.MalwareScanEnabled.ConnectionString);
        var sourceClient = blobServiceClient.GetBlobContainerClient(containerName).GetBlobClient(url);
        await sourceClient.DeleteIfExistsAsync(DeleteSnapshotsOption.IncludeSnapshots);
    }

The url in question is 6509eb0e-ed4f-4d94-0d07-08de1d4a6876/Gmail - =04 Bedankt voor je bestelling!_thumbnail.jpg

Error details:

The requested URI does not represent any resource on the server. RequestId:35eabfd8-901e-0036-7c20-5280aa000000 Time:2025-11-10T08:59:49.8875716Z Status: 400 (The requested URI does not represent any resource on the server.) ErrorCode: InvalidUri Content:  InvalidUriThe requested URI does not represent any resource on the server. RequestId:35eabfd8-901e-0036-7c20-5280aa000000 Time:2025-11-10T08:59:49.8875716Z Headers: Server: Windows-Azure-Blob/1.0 Microsoft-HTTPAPI/2.0 x-ms-error-code: InvalidUri x-ms-request-id: 35eabfd8-901e-0036-7c20-5280aa000000 x-ms-version: 2025-05-05 Date: Mon, 10 Nov 2025 08:59:49 GMT Content-Length: 244 Content-Type: application/xml

 

at Azure.Storage.Blobs.BlobRestClient.DeleteAsync(String snapshot, String versionId, Nullable`1 timeout, String leaseId, Nullable`1 deleteSnapshots, Nullable`1 ifModifiedSince, Nullable`1 ifUnmodifiedSince, String ifMatch, String ifNoneMatch, String ifTags, Nullable`1 blobDeleteType, CancellationToken cancellationToken) at Azure.Storage.Blobs.Specialized.BlobBaseClient.DeleteInternal(DeleteSnapshotsOption snapshotsOption, BlobRequestConditions conditions, Boolean async, CancellationToken cancellationToken, String operationName) at Azure.Storage.Blobs.Specialized.BlobBaseClient.DeleteIfExistsInternal(DeleteSnapshotsOption snapshotsOption, BlobRequestConditions conditions, Boolean async, CancellationToken cancellationToken) at Azure.Storage.Blobs.Specialized.BlobBaseClient.DeleteIfExistsAsync(DeleteSnapshotsOption snapshotsOption, BlobRequestConditions conditions, CancellationToken cancellationToken)

Expected behavior

I expect the request to always succeed, as we only care that the blob does not exist after processing.

Actual behavior

The request repeatedly fails. It is possible that the blob never existed in the first place.

Reproduction Steps

I'm not sure what's special about this case. It has been running in production for many months and this is the first time I have seen this issue.

Environment

dotnet 9 on linux - alpine-minirootfs-3.22.2-x86_64

[github-actions]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @amnguye @jalauzon-msft @jaschrep-msft @nickliu-msft @seanmcc-msft.

[nickliu-msft]

Hi @nlriverty, I have attempted to reproduce your issue to no success. Here is my test:

        public async Task DeleteIfExists_GetBlobClient()
        {
            await using DisposingContainer test = await GetTestContainerAsync();

            string url = "6509eb0e-ed4f-4d94-0d07-08de1d4a6876/Gmail - =04 Bedankt voor je bestelling!_thumbnail.jpg";
            BlobClient bobClient = test.Container.GetBlobClient(url);
            bool isDeleted = await bobClient.DeleteIfExistsAsync(DeleteSnapshotsOption.IncludeSnapshots);
            // isDeleted is false and the above request does not fail
        }

I am not seeing your failure. Maybe it has to do with the containerClient construction? Can you provide me what containerName is set as? Is it an url or the name of an existing container?