OrchardCMS/OrchardCore · error · FileStoreException

Cannot create file ' ' because it already exists.

Error message

Cannot create file '{path}' because it already exists.

What it means

CreateFileFromStreamAsync validates that the destination blob does not already exist when overwrite=false, throwing this FileStoreException. It is a pre-condition check done client-side via ExistsAsync before any upload is attempted.

Solutions

1. Pass overwrite: true if replacing the existing file is intended.
2. Check existence first with GetFileInfoAsync(path) and generate a unique name (append a number/timestamp) when the file exists.
3. Ensure media upload flows configured with uniqueness settings append unique suffixes to filenames.
4. Namespace paths by content item or folder to reduce name collisions.

Example fix

// before
await fileStore.CreateFileFromStreamAsync("media/logo.png", stream);
// FileStoreException if logo.png exists
// after
var existing = await fileStore.GetFileInfoAsync("media/logo.png");
var name = existing != null ? $"media/logo-{DateTime.UtcNow:yyyyMMddHHmmss}.png" : "media/logo.png";
await fileStore.CreateFileFromStreamAsync(name, stream);

if (await fileStore.GetFileInfoAsync(path) != null)
{
    // pick a unique name or set overwrite: true
    path = $"{baseName}-{Guid.NewGuid():N}{extension}";
}

try
{
    await fileStore.CreateFileFromStreamAsync(path, stream, overwrite: false);
}
catch (FileStoreException)
{
    // file already exists — rename or overwrite
}

When it happens

Trigger: Calling IFileStore.CreateFileFromStreamAsync(path, stream, overwrite: false) when a blob already exists at that path. Also occurs implicitly in CreateFileFromStream callers like media upload flows that pick an existing file name.

Common situations: Re-uploading media with the same filename without renaming; two users/tenants importing files with identical names concurrently; running an import twice; restoring content into a container that already holds the target blob.

Understand the failure class

Background: "already exists" / EEXIST / FileAlreadyExistsException: what the 'file already exists' error means and how to fix it — this error's family across 37 libraries.

Related errors

• Cannot create directory because the path
• Cannot copy file ' ' because a file already exists in the…
• Cannot copy file ' ' to ' '.
• Cannot get file stream because the file
• Cannot create file ' ' because it already exists.

AI-assisted analysis of OrchardCMS/OrchardCore@4306c0717f (2026-09-13). Data as JSON: /api/errors/fec1eacee2aa908b. Report an issue: GitHub.

Appendix: source

Thrown at src/OrchardCore/OrchardCore.FileStorage.AzureBlob/BlobFileStore.cs:667

        }
    }

    // Reduces the need to call blob.FetchAttributes, and blob.ExistsAsync,
    // as Azure Storage Library will perform these actions on OpenReadAsync().
    public Task<Stream> GetFileStreamAsync(IFileStoreEntry fileStoreEntry)
    {
        return GetFileStreamAsync(fileStoreEntry.Path);
    }

    public async Task<string> CreateFileFromStreamAsync(string path, Stream inputStream, bool overwrite = false)
    {
        try
        {
            var blob = GetBlobReference(path);

            if (!overwrite && await blob.ExistsAsync())
            {
                throw new FileStoreException($"Cannot create file '{path}' because it already exists.");
            }

            _contentTypeProvider.TryGetContentType(path, out var contentType);

            var headers = new BlobHttpHeaders
            {
                ContentType = contentType ?? MediaTypeNames.Application.Octet,
            };

            await blob.UploadAsync(inputStream, headers);

            return path;
        }
        catch (FileStoreException)
        {
            throw;
        }
        catch (Exception ex)

View on GitHub (pinned to 4306c0717f)