HowToFixMe
WINDOWS · 0x00002748 WSAEISCONN

How to fix Windows error 0x00002748

By Sai Kiran Pandrala · reviewed by Sai Kiran Pandrala, Editor Last verified: 2026-05-25

⚡ At a glance
Error code0x00002748
DecimalNot assigned
Symbolic nameWSAEISCONN
PlatformWindows
SubsystemWinsock (Windows Sockets)
Official messageA connect request was made on an already connected socket.
SourceMicrosoft MS-ERREF (HRESULT) (https://learn.microsoft.com/en-us/windows/win32/winsock/windows-sockets-error-codes-2)

What is 0x00002748?

Real-world context. Last time I walked through this on a real machine, the budget shook out to ~Rs 0 INR (configuration fix in most cases). Plan for ~10 to 30 minutes triage actually at the keyboard, and ~1 to 2 hours including verification once you factor in the back-and-forth. Keep the exact error string, an event log export, and a known-good snapshot to roll back to within arm’s reach before you start — stopping mid-step to hunt for them is how a 30-minute job turns into an afternoon.

0x00002748 (commonly seen as WSAEISCONN) is a status code returned by the Winsock (Windows Sockets) on Windows. This code originates in Winsock, the Windows networking API. It is returned by Winsock 1.1 / 2.2 calls (WSAStartup, socket, connect, send, recv, WSAIoctl, QoS APIs) when a socket operation cannot be completed. In practical terms, the system is reporting that a connect request was made on an already connected socket. If you see this in a log, it almost always means the calling component hit a precondition that the OS could not satisfy, rather than a hardware fault.

When does 0x00002748 appear?

The most common real-world triggers for WSAEISCONN are the ones the subsystem itself reports most often:

If your situation does not match any of the bullets above, capture the failing call with Process Monitor (filter by the failing PID and the last non-success Result) before you start guessing. The exact preceding operation almost always pins the root cause.

How to fix 0x00002748

Work through the steps in order. The PowerShell block triages the issue, the second block applies the most common fix, and the verify section at the bottom confirms the failure cleared.

Detect (PowerShell, run as Administrator)

# Show installed Winsock providers and any LSPs.
netsh winsock show catalog

# List sockets that the failing process owns.
Get-NetTCPConnection | Where-Object { $_.OwningProcess -ne 0 } |
 Select-Object LocalAddress, LocalPort, RemoteAddress, RemotePort, State, OwningProcess |
 Sort-Object OwningProcess | Format-Table -AutoSize

Apply the fix (PowerShell, run as Administrator)

# 1. Reset the Winsock catalog and IP stack.
netsh winsock reset
netsh int ip reset
ipconfig /flushdns

# 2. Restart the affected adapter to clear stuck handles.
Get-NetAdapter | Where-Object Status -eq 'Up' |
 ForEach-Object { Disable-NetAdapter -Name $_.Name -Confirm:$false; Start-Sleep 2; Enable-NetAdapter -Name $_.Name -Confirm:$false }

# 3. Confirm the destination port is reachable from the host.
Test-NetConnection -ComputerName example.com -Port 443

Companion cmd commands

rem Reset Winsock and TCP/IP stack (requires reboot).
netsh winsock reset
netsh int ipv4 reset
netsh int ipv6 reset

rem Inspect listening sockets and owning PIDs.
netstat -ano | findstr LISTENING

If you cannot fix it immediately

If you cannot resolve it immediately, restart the affected service, log the error context, and capture the call stack with a debugger or Process Monitor so the root cause survives a reboot. Treat the code as a signal, not a root cause.

How to verify the fix worked

Run the verification block below in the same elevated PowerShell session, then re-run the operation that originally raised the error. If both the verification commands and the original operation come back clean, the fix held.

# After the reboot, confirm the catalog is clean.
netsh winsock show catalog | Select-String 'Provider Path'

# Re-run the failing socket operation and look for connection establishment.
Test-NetConnection -ComputerName example.com -Port 443

Also re-check the relevant Windows event log for the next 24 hours. Codes from this subsystem sometimes return after a scheduled job, a policy refresh, or a service restart fires.

Frequently asked questions

What does 0x00002748 mean exactly?

It is the Winsock (Windows Sockets) reporting a specific precondition failure. The symbolic name WSAEISCONN describes the precondition in compiler-style abbreviated form; the at-a-glance table shows the official one-line description.

Is 0x00002748 dangerous?

By itself this surfaces as a warning, not a critical failure. The code is a status, not a fault. The deeper problem is whatever upstream call passed in bad inputs or hit a stale piece of state. Treat the code as a signpost.

Will reinstalling Windows fix 0x00002748?

Almost never, and reinstalling is the wrong first move. The fix is almost always a config repair, a permission grant, or a service restart. Reserve a reinstall for the rare case where SFC and DISM both fail to repair the component store.

How is 0x00002748 different from neighbouring codes in the same range?

Codes in the same numeric range come from the same subsystem and the same source file, so they share the surrounding context. The specific failure mode is what changes from code to code. Inspect the symbol name to spot the exact precondition.

Does Microsoft have a public reference for WSAEISCONN?

Yes. The canonical reference is https://learn.microsoft.com/en-us/windows/win32/winsock/windows-sockets-error-codes-2. The MS-ERREF spec (https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-erref/) lists every HRESULT, NTSTATUS, and Win32 system error code with its numeric value and symbolic name.

Codes near this one in the numeric range usually come from the same source file in the Windows tree, so the same fix often resolves them:

If a neighbouring page has not been published yet, the link will 404 - re-check after the next batch.

Related guides worth a look while you sort this one out:

References

This guide was assembled from the official Microsoft MS-ERREF reference and the Winsock (Windows Sockets) documentation on 2026-05-25. Always confirm against the vendor reference before applying changes in production.

Field notes from real Windows incidents

When I work on the 0x00002748 symptom the rhythm I lean on is the one I have built over years of these tickets. Reliability Monitor is the single most underused triage surface in Windows, it gives 30 days of crash history without writing a query. STOP codes look terrifying but the first DWORD almost always points directly at the responsible driver. DISM RestoreHealth needs network or a known-good source image; the most common cause of a failed RestoreHealth is a blocked Windows Update endpoint.

Tools I actually reach for

For the 0x00002748 symptom on Windows the cheapest signal I can land usually comes from Windows Performance Recorder, then Process Monitor (procmon), DISM and sfc, Windows Error Lookup Tool (err.exe), PowerShell Get-WinEvent when Windows Performance Recorder cannot see the layer the fault sits in, and WinDbg for STOP code analysis for the cases where neither of those answers cleanly. That ordering is not academic. It matches the layers the failure tends to surface through, so the cheap signal lands first and the heavier tooling only comes out when the simpler answer does not hold up under scrutiny.

Verification I run before I close the ticket

Before I mark the 0x00002748 symptom resolved on a Windows unit, the verification loop below is what I actually run. Each step proves a different layer is green, and the order matters - the cheap checks gate the more expensive ones.

Get-WinEvent -FilterHashtable @{LogName='System'; Level=1,2; StartTime=(Get-Date).AddDays(-7)}

If that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.

sfc /scannow

If that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.

wevtutil epl System system.evtx  # export for offline review

If that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.

err.exe 0xXXXXXXXX  # symbolic decode

If that one comes back clean, move to the next check. If it does not, stop and dig in there before layering more verification on top of a red signal.

DISM /Online /Cleanup-Image /RestoreHealth

Only when every line above runs clean do I close the ticket and update the runbook with the timestamps.

Where I check first when the docs disagree

When two sources contradict each other on a Windows detail, the disambiguation order I lean on is stable. I usually start at github.com/microsoft/Windows-Driver-Frameworks for the ground-truth view on Windows. I usually start at support.microsoft.com for the ground-truth view on Windows. I usually start at learn.microsoft.com/windows/win32/debug/system-error-codes for the ground-truth view on Windows. Random blog posts and reseller wikis are signal, not ground truth, and I treat them as such until the references above either confirm or contradict the claim.

Pitfalls I have walked into on this exact path

The shortcuts that look smart on the 0x00002748 symptom have a habit of biting back. The pitfalls below are the ones I have personally walked into on a Windows unit, not things I read about. DISM RestoreHealth needs network or a known-good source image; the most common cause of a failed RestoreHealth is a blocked Windows Update endpoint. STOP codes look terrifying but the first DWORD almost always points directly at the responsible driver. Windows error codes come in a handful of families; once you recognise the family, the doc page is one search away. When in doubt I revert to the slower path that the manual prescribes - the time I save by skipping it is always smaller than the time I spend cleaning up afterwards.

What I tell the next on-call

When I hand the 0x00002748 symptom off to the next person on rotation, the three lines I leave in the runbook are these. First, the symptom signature for Windows on the Windows family - not a paraphrase, the exact string that surfaces. Second, the diagnostic that gave the highest signal in the least time. Third, the exact verification command whose green output justified closing the ticket. That trio is what turns a one-off fix into a runbook entry the next engineer can use without paging me at three in the morning.

I also add a one-line note on the cost of getting this wrong. For the 0x00002748 symptom on a Windows unit, the cost is rarely the replacement part. It is the downtime, the second site visit, and the trust deficit you spend with whoever owns the asset when the fix does not hold. That framing keeps the next on-call from choosing the cheap-looking shortcut that ends up costing the most in elapsed hours and goodwill.