S/MIME Troubleshooting

S/MIME Troubleshooting

If you have S/MIME problems, this article will help you. We have compiled the most common errors and their solutions.
 

Quick Problem Overview

• ❌ Certificate import fails
• ❌ "Encrypt" checkbox is grayed out/disabled
• ❌ Exchange with partner doesn't work
• ❌ Partner doesn't appear in Public Certificates
• ❌ Encrypted email can't be decrypted
• ❌ Signature shows as invalid
• ❌ Duplicate or corrupted certificates in keyring
• Complete system restart

 

❌ Problem: Certificate import fails

Problem

• An error message appears when selecting certificate
• Import dialog closes or shows "Import Error"
• Password is shown as incorrect, even though it's correct

Possible Causes & Solutions

1. Wrong password

• Problem: The entered password is not the import password
• Solution:
  • Use the password from your certification authority (CA)
  • NOT your eclipso Mail Europe password!
  • Check for CAPS LOCK and special characters
  • Copy the password directly from the CA's email

2. Wrong file format

• Problem: The file is not in .pfx or .p12 format
• Solution:
  • Check file extension: .pfx or .p12 (not .cer, .crt, .pem)
  • If your CA provided a different format, convert it
  • Windows: Use Openssl: openssl pkcs12 -in file.pem -out file.pfx
  • Contact your CA for a .pfx file

3. Corrupted certificate file

• Problem: The .pfx file is corrupted or incomplete
• Solution:
  • Download the certificate file again from your CA
  • Check for download errors (verify size)
  • Try from a different computer
  • If errors persist: Contact your certification authority

4. Browser cache problem

• Problem: Browser cache is outdated or corrupted
• Solution:
  • Clear browser cache (Ctrl+Shift+Del)
  • Clear browser history
  • Try in a different browser
  • Use private/incognito mode

 

❌ Problem: "Encrypt" checkbox is grayed out/disabled

Problem

• The "Encrypt" checkbox cannot be clicked
• The checkbox is grayed out or disabled
• Message: "Not available" or "Disabled"

Cause & Solution

The checkbox is disabled because:

• ❌ The recipient's public key is NOT stored
• ❌ You haven't done a signed exchange yet
• ❌ The exchange failed

✅ SOLUTION:

• Step 1: Perform the exchange
  • see exchange guide
  • Send a signed email (✅ Sign, ❌ Encrypt)
  • Wait for signed reply
• Step 2: Check Public Certificates
  • Settings → Email → Keyring
  • Click "Public Certificates"
  • Check if recipient appears in list
  • If NOT → Repeat exchange!
• Step 3: After successful exchange
  • The checkbox should now be active
  • You can now send encrypted

What if it still doesn't work?

• See: Exchange with partner doesn't work
• See: Complete system restart

 

❌ Problem: Exchange with partner doesn't work

Problem

• You send signed email, partner doesn't reply
• After exchange, partner does NOT appear in Public Certificates
• Signature shows as invalid

Common Causes & Solutions

1. Partner doesn't reply signed

• Problem: Partner sends reply WITHOUT signature
• Solution:
  • Contact your partner by phone or in person
  • Explain the process: see exchange guide
  • Partner must ALSO:
    • Import their certificate
    • Reply with ✅ Sign, ❌ Encrypt

2. You activated encryption instead of signature

• Problem: You set the boxes wrong when sending
• Solution:
  • ✅ Sign: ENABLE
  • ❌ Encrypt: DISABLE
  • Try again

3. Partner has no certificate imported

• Problem: Partner can't reply signed because no certificate
• Solution:
  • Partner must first import their certificate
  • Share this guide with partner: Import S/MIME Certificate
  • Then repeat exchange

4. Certificates are expired or invalid

• Problem: Your or partner's certificate is expired
• Solution:
  • Check validity period in your certificates
  • Settings → Email → Keyring → Own Certificates
  • If expired: Request new certificate from your CA
  • Import the new certificate

5. Email was marked as spam

• Problem: Signed email lands in spam and partner doesn't see it
• Solution:
  • Ask partner to check spam folder
  • Partner should save you as contact (whitelist)
  • Check your sender address

 

❌ Problem: Partner doesn't appear in Public Certificates

Problem

• You exchanged signed emails
• But partner's name is missing from "Public Certificates"
• Encryption is still not possible

Solution Steps

Step 1: Check if email from partner arrived

• Open the email from your partner
• Check if "Signature OK" or "✅ Verified" symbol is shown
• If NOT: Signature was not recognized

Step 2: Process email manually

• Sometimes eclipso Mail Europe doesn't save certificates automatically
• Click on signature info in the email
• Look for "Save Certificate" or "Save Public Key"
• If available: Click it

Step 3: Refresh Public Certificates

• Go to: Settings → Email → Keyring
• Click "Public Certificates"
• Refresh page (F5 or Ctrl+R)
• Partner should appear now

Step 4: Repeat exchange

• If partner still not visible
• Send signed email AGAIN
• Wait for reply
• Check Public Certificates again

 

❌ Problem: Encrypted email can't be decrypted

Problem

• You receive encrypted email from partner
• Email shows: "❌ Decryption failed" or unreadable
• You see only encrypted text

Possible Causes & Solutions

1. You don't have matching certificate

• Problem: Your certificate doesn't match the key
• Solution:
  • Partner encrypted with the WRONG public key
  • Check: Which certificate did partner get from you?
  • You might have multiple certificates
  • See: Duplicate or corrupted certificates

2. Certificate is corrupted or invalid

• Problem: Your private key is corrupted
• Solution:
  • Perform a complete restart
  • Re-import your certificate
  • Contact support

3. Certificate is expired

• Problem: Your certificate is no longer valid
• Solution:
  • Request new certificate from your CA
  • Import the new certificate

 

❌ Problem: Signature shows as invalid

Problem

• Message: "❌ Signature invalid" or "⚠️ Signature couldn't be verified"
• Email from partner shows "Warning"
• Signature is not trustworthy

Possible Causes & Solutions

1. Certificate is expired

• Problem: Partner's certificate is no longer valid
• Solution:
  • Contact your partner
  • Partner should request new certificate
  • Repeat exchange with new certificate

2. Email was modified

• Problem: Email or signature was modified after sending
• Solution:
  • This is a security feature - email was damaged in transit
  • Ask partner to send again
  • This is NORMAL if email was corrupted

3. Wrong certificate store

• Problem: Partner's certificate is not stored correctly
• Solution:
  • Delete partner's public certificate
  • Ask partner to send signed email
  • Certificate will be stored again

 

❌ Problem: Duplicate or corrupted certificates in keyring

Problem

• You see the same certificate multiple times in keyring
• Certificate is named e.g. "My Name (1)" and "My Name (2)"
• Certificates are corrupted or incomplete
• Encryption doesn't work properly

⚠️ THIS IS THE PROBLEM FROM YOUR TICKET!

If you have a new account after import and old database still has certificates, this can happen exactly.

Solution Steps

Step 1: Create backup

• Back up your important certificates
• Settings → Email → Keyring
• Click your certificate
• Click "Export" or "Download"
• Save file securely

Step 2: DELETE ALL certificates (the faulty ones)

• Settings → Email → Keyring
• Delete BOTH:
  • Own Certificates (Type 2)
  • Public Certificates (Type 1)
• Also the duplicates!
• Refresh page (F5)
• ✅ Keyring should now be empty

Step 3: Import new certificate

• Settings → Email → Keyring
• Click "Import Certificate"
• Select your .pfx or .p12 file
• Enter import password
• ✅ New certificate imported

Step 4: Exchange with partner

• Follow the exchange guide
• Send signed email
• Wait for reply
• Check Public Certificates

Step 5: Test encryption

• Send encrypted email to partner
• ✅ It should work now!

What if it still doesn't work?

• See next point: Complete system restart
• Contact support with details

 

Solution: Complete System Restart

When to use?

This solution is radical, but works when:

• ❌ Duplicate/corrupted certificates present
• ❌ Nothing else helps
• ❌ Certificates still there after deletion
• ❌ Exchange doesn't work

Step 1: Back up all data

Export all certificates you need:

• Settings → Email → Keyring
• Select EACH certificate
• Click "Export"
• Save each export locally

Note down:

• Import passwords for all certificates
• Email addresses of your partners
• Which certificates belong to whom

Step 2: Complete deletion

Delete completely:

• Settings → Email → Keyring
• Delete: ALL Own Certificates (Type 2)
• Delete: ALL Public Certificates (Type 1)
• Refresh page multiple times (F5, F5, F5)
• ✅ Keyring should now be completely EMPTY

If certificates keep reappearing:

• Clear browser cache (Ctrl+Shift+Del)
• Delete cookies
• Try private/incognito mode
• Try a different browser

Step 3: Restart session

• Log out (top right → Logout)
• Close browser completely
• Wait 10 seconds
• Open browser again
• Log in again
• Go to: Settings → Email → Keyring
• Check: Keyring should STILL BE EMPTY

Step 4: Re-import

Import your certificates again, ONE by ONE:

• Settings → Email → Keyring
• Click "Import Certificate"
• Select ONE .pfx or .p12 file
• Enter password
• ✅ Wait for "Successfully imported"
• Repeat with next certificate

Step 5: New exchange with partners

• You now have a clean system
• Contact all your partners
• Ask for exchange with new process
• Follow the exchange guide

Step 6: Test

• Send signed email to partner
• Wait for reply
• Check Public Certificates
• Send encrypted email
• ✅ It should work!

 

Still having problems?

Contact our support:

• Email: support [@] eclipso.net
• Tell us: Which problem you have
• Describe: Which solution steps you already tried
• Attach: Screenshots of error messages
• Mention: Which browser and operating system

Our team is happy to help! ????

Related Articles

• What is S/MIME and how does it work? ➜
• Import S/MIME Certificate ➜
• Exchange Digital Signatures ➜
• Activate S/MIME Encryption ➜