TechClassy

Windows Error & PC Diagnostic Tools

Diagnose a Windows error

Paste exactly what Windows showed. Get the confirmed facts, one safe check, and a recorded next move — stop, repeat once, add one fact, or escalate with a ready Evidence Pack.

Use the exact code, final message, Stop Code, driver filename, or final SFC/DISM line — not a description from memory.

Runs in this browser — no upload, no account, nothing stored

Ctrl/⌘ + Enter

Real cases
Resume a saved session — paste a Resume Capsule

The capsule is validated and restored only in this browser. An invalid capsule changes nothing.

Evidence before repair

One bounded loop — never an open-ended repair chain.

  1. Identify

    Paste the exact error. The result separates what Windows confirmed from what it does not prove.

  2. Check

    One read-only or reversible check, with the expected result, how to verify it, and the rollback.

  3. Record

    What the check produced — and separately, whether the original problem came back.

  4. Decide

    Stop and monitor, repeat once, record one missing fact, or escalate with the Evidence Pack.

Deliberately excluded: driver updaters, registry cleaners, dump uploads, and uncontrolled AI repair commands. Read the risk policy and review method.

Go straight to a focused route

Diagnostic routes

Error CheckerRecognize a code, exact message, driver filename, Stop Code, or command result and route it to the right diagnostic family. UpdateSeparate download, install, restart, servicing, space, connectivity, and upgrade rollback evidence. DeviceInterpret Device Manager status only after identifying the affected device category. BSODIdentify the confirmed bug-check family, capture recurrence context, and collect usable crash evidence without guessing a root cause. Command OutputParse the final SFC or DISM status locally and show the next evidence checkpoint before any administrator repair step. Driver filesIdentify what a named .sys file can establish—and what it cannot establish—before changing drivers or security software. Network & proxyDistinguish browser-only, proxy, VPN, DNS, and managed-network evidence without defaulting to destructive network resets. Windows SandboxCheck edition, Windows feature state, virtualization, hypervisor, and policy context before changing configuration.

Evidence readers

Event ViewerEvidence readerPaste one time-matched Event Viewer record as rendered text or XML and extract the provider, Event ID, time, level, faulting fields, and diagnostic tokens without uploading the event. Update / CBS logEvidence readerPaste a short WindowsUpdate.log, CBS.log, DISM, or servicing excerpt and extract timestamps, components, KBs, packages, error codes, and repeated error clusters without uploading the log. System informationEvidence readerPaste a bounded msinfo32 or DxDiag text report and extract the Windows build, system model, firmware mode, memory, DirectX, display-driver, and explicitly reported problem-device facts without uploading the report. Driver identityEvidence readerPaste bounded driverquery or PnPUtil enumeration text and extract driver, package, provider, class, version, signer, state, path, and device-relation facts without recommending a download or naming a culprit. Known issuesEvidence readerEnter a Windows version/build, installed KB, and exact symptom to compare them with a bounded, dated Microsoft Release Health snapshot without claiming that a matching record proves this device is affected.

Local-first utility

Privacy

The diagnostic parser, evidence readers, verification loop, and Evidence Pack run in your browser. TechClassy does not intentionally store the raw text you paste, Event Viewer or update-log excerpts, full command output, usernames, local file paths, dump files, device serial numbers, observations, parsed summaries, or generated Evidence Packs.

No advertising, analytics, session replay, account system, upload surface, or third-party diagnostic script is loaded in this release. Standard hosting security logs may contain request metadata such as time, requested path, and network information; diagnostic and evidence text is not sent as a URL parameter or API body by the tool.

Use boundary

TechClassy organizes evidence and reviewed next checks. It is not a substitute for Microsoft, an OEM, an employer's IT team, or a qualified repair professional. Results distinguish confirmed facts from possible causes and do not guarantee a repair.

Back up important data before making system changes. Stop when an action requires credentials, firmware changes, disk work, account recovery, or a command whose prerequisites you cannot verify.

Independent operation

This is a newly researched, independently operated diagnostic product. It does not claim to be the prior TechClassy editorial team or a continuation of prior authorship.

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