Azure Storage Explorer Alternative: Jam SQL Studio Compared

If you manage storage on its own and rely on AzCopy transfers, copying files between file shares, moving queue messages or a native Windows ARM64 build, Azure Storage Explorer covers more of that today. If your application keeps its data in a SQL database and a storage account side by side, if Table storage is part of your daily work, or if you want AI agents to work with storage under approvals you control, Jam SQL Studio is the tool to keep open. Both call the same Azure Storage APIs, so you can install both and use each for what it does best.

These are real gaps. If one of them is part of your routine, keep Azure Storage Explorer installed for it; both apps can open the same account at the same time.

• Windows on ARM. Azure Storage Explorer ships a native Windows ARM64 build. Jam SQL Studio's Windows build is x64 only.
• AzCopy. Azure Storage Explorer runs its transfers with AzCopy, can limit their bandwidth and copies the AzCopy command for a transfer to the clipboard. Jam SQL Studio uses its own transfer engine, with no bandwidth limit.
• Copying and moving on file shares. Azure Storage Explorer copies and pastes files and shares, also across accounts, renames and moves files on a share, and copies between blob containers and file shares. Jam SQL Studio's copy and paste covers blob containers and Data Lake; on file shares you download and upload again.
• Queue messages beyond peek and receive. Azure Storage Explorer moves messages between queues, requeues a message, imports messages from CSV and shows a queue's properties and metadata. Jam SQL Studio peeks, receives, adds, updates, deletes and clears messages.
• Finding blobs by index tags, and CORS rules. Azure Storage Explorer has a filter panel that finds blobs by their index tags, and edits each service's CORS rules. Jam SQL Studio sets and shows index tags but does not search by them, and has no CORS editor.
• Sign-in options and direct links. Azure Storage Explorer signs in through the operating system's authentication broker or with a device code, and opens storageexplorer:// links to a resource. Jam SQL Studio signs in through the browser, with a service principal or with az login, and has no direct links.

Neither tool works with Cosmos DB. Microsoft announced the deprecation of Azure Storage Explorer's Cosmos DB integration in August 2020, retired it in version 1.22.0 (December 2021), and points Cosmos DB users to the Azure portal and the standalone Cosmos DB Explorer.

Jam SQL Studio is database-first, and that is the reason it suits a certain kind of Azure Storage work: an application's orders sit in SQL Server or PostgreSQL, its invoices sit in a blob container, its background jobs pass through a queue, and its settings live in Table storage. Here is what that looks like in practice. The Azure Storage client overview walks through each service on its own.

Storage accounts next to your SQL databases

A storage account is a connection in the same Object Explorer as your SQL connections, with Blob Containers, File Shares, Queues and Tables folders under it. Checking an order row and then the invoice blob it points at happens in one window, with the same tabs, pins and search. Open storage tabs are saved with your session, so resuming the session from the Sessions dialog after a restart reopens them in the same container, folder or table.

Preview and edit files without downloading them

Turn on Preview and the file you select in a container, a Data Lake file system or a file share shows in a pane next to the list: JSON as an expandable tree (the same viewer the query results grid uses for JSON cells), formatted or as stored, Markdown rendered, configuration files and code with syntax highlighting, and images, video and audio. Arrow keys move through the list and the pane follows. Edit changes a text file in place; Save writes it only if its ETag still matches the version you opened, and keeps the blob's headers, metadata and index tags, or a Data Lake file's ACL. Save a copy puts your text under a new name or in another container. See Preview and edit files.

Table entities in a real data grid

An Azure table opens in the Table Explorer grid that Jam SQL Studio uses for SQL tables. Every property keeps its Azure type: Int64 values stay exact, date-times keep all seven fractional digits (cells show your local time; the tooltip, copy and export keep the exact value), and a property an entity does not have shows as ∅, which is different from an empty string. You filter with filter chips or a raw OData filter, and both go through the same validator, which enforces Azure's limit of 15 comparisons before anything is sent.

In edit mode you add entities and properties, change values and delete entities, then save the drafts together. Each update is conditional on the entity's ETag, so if someone else changed the entity first you get a comparison of the original, current and proposed values with Reload, Overwrite anyway and Keep draft. Export writes the selected rows, the loaded page or every entity matching the filter to CSV, JSON or Excel. Properties can carry the same enum, JSON and loose relationship declarations as SQL columns, so a CustomerId property that points at a customers table's RowKey, with the PartitionKey fixed by a target filter, shows the customer's name and opens that entity.

Transfers you can cancel, resume and restart

Uploads, downloads and deletes run as background jobs in Jam SQL Studio's built-in transfer engine. The chip at the bottom of the window opens the Transfers drawer with item and byte progress, throughput and the attempt count. Cancel keeps a partial download on disk and Resume requests only the missing bytes; if the blob changed in the meantime, the download starts over and says so. Restart sends the unfinished items again from the first byte and keeps the ones that completed. A job that finished with failed items lists them with a per-item Retry, and jobs survive an app restart.

Test Connection names the role that is missing

With Microsoft Entra ID, listing containers, tables and queues needs only a management role such as Reader, while reading what is inside them needs a data role such as Storage Blob Data Reader. Microsoft's Storage Explorer troubleshooting guide explains the same split. Jam SQL Studio's Test Connection probes each service separately and follows each listing with one data read (a blob page, an entity or a peeked message), then says what it read. When every item it checked was refused, the row says the identity can list but not read and names the missing data role; when only some were readable, it reports partial data access. The service folder in the Object Explorer carries the same result as a badge, and a read refused later names the role and where to assign it. The guide to Azure Storage permission errors maps each error message to the role it needs.

If the identity may read the account keys, you can set the connection's Data access to the account key instead, or accept the same offer under the error. Jam SQL Studio then reads the key through Azure Resource Manager each time it connects and never saves it. The default is the other way round in Azure Storage Explorer: according to Microsoft's security guide, it attempts to use account keys whenever they are available, unless you turn on Settings → Services → Storage Accounts → Disable Usage of Keys. Jam SQL Studio uses an account key for data access only on a connection where you turned that on.

Data Lake ACLs: the effective permissions before you save

On an account with a hierarchical namespace, Manage access… edits the owner, owning group, access entries and default entries of one file or directory. The Effective column shows what each entry grants once the mask applies, the mask stays as loaded while you edit entries, and before saving the editor lists every change in effective permissions and marks the ones that widen access. Azure applies the save only while the path still has the version (ETag) the editor loaded, but an ACL change does not change that version, so right before writing Jam SQL Studio reads the ACL again and refuses the save if it differs from the one the editor loaded. Azure has no condition on the ACL itself, so a change another client makes between that read and the write is not detected.

Propagate access… merges, replaces or removes entries on a directory and everything under it as a job in the Transfers drawer, in batches of up to 2,000 paths. Replace and Remove ask you to type the directory name, paths Azure refuses are listed with Retry, and a cancelled or interrupted job can Resume from the last recorded batch. Azure cannot make a recursive ACL change conditional, so there is no undo, and the dialog states exactly what is checked before and during the job. Microsoft's ACL guide for Storage Explorer notes that of its connection methods only the subscription sign-in supports managing ACLs; in Jam SQL Studio the editor works on a Microsoft Entra ID or account-key connection.

SMB and NFS file shares without mounting

The File Shares folder lists SMB and NFS shares alike, and everything goes through the Azure Files REST API, so nothing is mounted on your machine. Uploads write each file under a hidden temporary name and then give it its final name without replacing a file that appeared there in the meantime, so a cancelled upload can resume. Downloads keep each file's last-write time. A delete confirmation says how many snapshots the share has, because Azure Files has no soft delete for individual files; snapshots open as read-only tabs. On NFS shares Azure's REST API cannot replace an existing file, so a name collision offers Skip or Keep both.

Azurite and local development

Jam SQL Studio connects to the Azurite emulator with its well-known development account and also finds Azurite containers running in Docker. The guide to running Azurite in Docker and browsing it has a working compose file and the errors people hit when they connect.

Read-only connections

Marking a connection read-only (Access → Open read-only in the connection form) applies to you as well as to agents. Browsing, downloading and peeking stay available; every upload, delete, tier change and queue or entity change is disabled with the reason, and the SAS dialog offers only permissions that cannot modify anything. It is a simple way to look at a production account without the risk of a stray drag and drop.

AI agents over MCP, with approvals that name every target

Jam SQL Studio's local MCP server gives agents such as Claude Code, Codex and Cursor forty-one storage_* tools: listing and reading blobs, finding them by name, downloads and transfer status, uploads, deletes, copy and move, leases, snapshots, versions and undelete, queues, SAS generation, Table entities, counts and table copies, file shares, Data Lake ACLs, and managed disks. Each connection's permission level decides what an agent may do: Block refuses every storage tool, Read-only refuses writes, and Confirm opens an approval dialog for every write. Every approval lists every target the write touches once, in full, in a list you scroll, with a container or share deletion listed first; a call can name at most 1,000 items. Table writes list the entities by PartitionKey and RowKey but never show property values, an agent never picks where a download is saved, and a generated SAS token stays in the app.

We found no agent integration in Azure Storage Explorer's documentation or release notes. Microsoft does publish a separate Azure MCP Server whose storage group has seven tools at the time of writing: get storage accounts, blob containers, blobs and tables, create an account or a container, and upload a blob. It is a good fit for agents that work across Azure resources; Jam SQL Studio's tools are for agents that work on the storage connections you already have open, under the permission level you set for each one.

If Azure Storage Explorer stops with Object reference not set to an instance of an object (some people remember it as “object reference not found”), the message comes from .NET. It is the text of a NullReferenceException, which .NET throws when code uses an object that was never created. Azure Storage Explorer needs a .NET 10 runtime since version 1.42.0 (prerequisites). When the exception happens during sign-in, the error reads “Unable to sign in:” followed by that message. We have run into this error ourselves.

When it has been reported

The public reports we found are about sign-in. Since Storage Explorer 1.44.0 (released 2026-06-29), a series of issues in Microsoft's AzureStorageExplorer GitHub repository describe the same failure: after Sign in with Azure and choosing an Azure environment, the app reports “Unable to sign in: Object reference not set to an instance of an object.” Most of them come from Apple Silicon Macs. Issue #9114 describes the steps on version 1.44.0. Issue #9118 includes the stack trace, a System.NullReferenceException in the authentication broker code of Microsoft's identity library, and says version 1.43 signed in without it. The 1.45.0 release notes list a fix for “a sign-in failure on macOS (Apple Silicon) that affected some centrally managed devices”, and reports against 1.45.0 and 1.46.0 followed: issue #9189, issue #9194 (1.46.0, filed with the x64 architecture on 2026-09-17) and issue #9203 (1.46.0 on an Apple Silicon Mac, 2026-09-28). A GitHub search on 2026-09-30 finds 11 issues opened since 1.44.0 that contain the message.

Workarounds that are publicly documented

1. Switch the sign-in method. Open Settings (the gear icon) → Application → Sign-in and set Sign in with to Default Web Browser. The reporter of issue #9114 found that sign-in succeeded after switching from Authentication Broker, and Microsoft's sign-in guide recommends Default Web Browser on macOS and Linux, or if you are having issues with the authentication broker option.
2. Go back to 1.43. The reporter of issue #9118 says downgrading to 1.43 resolved it immediately. The project's GitHub releases page lists earlier versions.
3. Reset the sign-in state. Microsoft's troubleshooting guide describes a general reset for sign-in loops: Help → Reset with Authentication selected, then restart. If that does not help, remove all accounts, close the app, delete the .IdentityService folder, on macOS or Linux also the Microsoft.Developer.IdentityService keychain entry, and start again. The guide lists these steps for reauthentication problems in general, not for this message in particular.
4. Attach without signing in. In the Connect dialog, a storage account can be attached with its account name and key or a SAS connection string, and a single container, share, queue or table with a SAS URL. None of these goes through the sign-in flow. They do not cover Data Lake ACL management, which in Azure Storage Explorer needs the subscription sign-in.

Jam SQL Studio as another way in

If you need your data while sign-in is failing, Jam SQL Studio is an alternative. Its Microsoft Entra ID sign-in is a separate implementation built on Azure's Identity library for JavaScript: an interactive browser sign-in, a service principal, or the account you already signed in with through az login. It also connects with an account key, a connection string or a SAS URL, and Browse Azure lists the storage accounts in your subscriptions. Both tools call the same Azure Storage APIs, so there is nothing to migrate, and you can go back to Azure Storage Explorer whenever you like.

• You run large transfers with AzCopy or need a bandwidth limit → Azure Storage Explorer.
• You copy, rename or move files on file shares, or move messages between queues → Azure Storage Explorer.
• Your application uses a SQL database and a storage account together → Jam SQL Studio: one window, one set of connections.
• Table storage is part of your daily work → Jam SQL Studio: draft edits with a comparison when someone else changed the entity first, Excel export, and relationship lookups between tables in the Table Explorer grid.
• You want AI agents to read or change storage → Jam SQL Studio, with the connection's permission level deciding what an agent may do.
• You change Data Lake ACLs recursively → Jam SQL Studio, for the effective-permission list before saving and propagation jobs you can resume.
• You work on a Linux ARM64 machine → Jam SQL Studio, which has native ARM64 Linux packages. On Windows on ARM → Azure Storage Explorer, which has a native ARM64 Windows build.
• You are not sure → install both. Azure Storage Explorer is free, and Jam SQL Studio is free for personal, non-commercial use and has a 14-day Pro trial for work.

The Azure Storage guide covers every Jam SQL Studio dialog mentioned here, and the launch post walks through the release with screenshots.