Quick Answer
MCA21 V3 requires a Class 3 DSC in the Current User certificate store with a valid private key. Use Chrome or Edge (not Firefox). Ensure your eToken driver is installed and the Smart Card service is running. If DSC still not detected, clear browser cache and retry.
Why DSC Fails on MCA21 V3
MCA21 V3 moved from the older Java-based applet to a browser-native certificate picker. This means your DSC must now be accessible via the Windows CAPI certificate store (certmgr.msc), not a separate Java plugin.
- Class 3 DSC required (Class 2 is no longer accepted for company filings)
- Certificate must be in Current User → Personal store
- Private key must be attached (key icon visible in certmgr.msc)
- Browser must support Windows certificate API: use Chrome or Edge, NOT Firefox
Step-by-Step Fix for MCA21 DSC Error
Work through these steps to get your DSC recognized by the MCA21 V3 signing dialog.
- Open certmgr.msc and verify your DSC appears under Personal → Certificates with a key icon
- Check expiry date — MCA21 requires a valid (non-expired) Class 3 DSC
- Open Chrome → Settings → Privacy and Security → Security → Manage Certificates — confirm DSC is listed
- Clear Chrome cache (Ctrl+Shift+Del → All time → Cached images and files)
- On MCA21 V3, click the signing button and wait 10–15 seconds for the certificate picker to load
DSC Not Showing in MCA21 Certificate Picker
If the certificate picker opens but your DSC isn't listed, the token or service layer usually needs attention.
- Ensure eToken driver (SafeNet SAC, ePass PKI Client, or WatchData driver) is installed and token is plugged in
- Run services.msc → Smart Card → Start/Restart the service
- If using a .pfx DSC (soft token): import via certmgr.msc → Personal → Certificates → Import
- Disable Chrome extensions temporarily — some extensions block certificate access
Diagnostic sequence
Run each step in order. Stop at the first failing expectation — that's where the root cause lives.
1. Verify DSC in Current User store
certmgr.msc → Personal → Certificates
Expected: Class 3 DSC appears with a key icon and a future expiry date
2. Confirm the Smart Card service is running
services.msc → Smart Card (SCardSvr)
Expected: Status Running, Startup type Automatic; restart after plugging in the token
3. Confirm the browser sees the certificate
Chrome → Settings → Privacy and Security → Security → Manage Certificates → Personal
Expected: Your DSC is listed and selectable in Chrome/Edge
Frequently asked questions
Does MCA21 V3 work with Firefox?
No. MCA21 V3 uses the browser's native Windows certificate store access, which Firefox does not support. Use Google Chrome or Microsoft Edge.
My Class 3 DSC is valid but MCA21 says 'No valid DSC found' — why?
The most common cause is that the certificate is installed under Local Machine store instead of Current User. Re-import the .pfx file and choose 'Current User' as the store location.
How do I check if my DSC is Class 2 or Class 3?
Open certmgr.msc, right-click the certificate → Properties → Details tab → Subject field. The OU (Organizational Unit) field will say 'Class 2' or 'Class 3'.
You might also need
More fix guides in DSC and related areas.
Still seeing this error?
If these steps don't isolate the root cause inside your environment, an independent consultant can run a structured PKI diagnostic with you over a screen-shared session and deliver a written report identifying root cause, remediation, and — where relevant — the next responsible party (CA, internal IT, or software vendor).
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