Tag: login prompt

Applies to: CyBlock · When activity isn’t logged by username, or employees get browser login prompts.

CyBlock identifies users automatically via NTLM as their traffic passes through the proxy. When that identification fails, you’ll see one or both of these symptoms:

• Usernames are blank or show as IP addresses in CyBlock activity and reports.
• Employees get a pop-up username/password prompt in Edge or Chrome when browsing — even to everyday sites.

Both symptoms mean CyBlock isn’t successfully identifying the user. Work through the two areas below in order: first confirm CyBlock’s own authentication rule, then (if users are being prompted) the Windows/browser configuration.

(If usernames are appearing but all fall under Ungrouped IDs, that’s a different issue — IDs are captured but not organized into your Groups and IDs tree. See the Terms Glossary for Ungrouped IDs.)

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Step 1 — Check the CyBlock Authentication Manager rule

Start here. CyBlock needs an NTLM authentication rule to identify users.

1. Go to User Management → Authentication → Authentication Manager.
2. Open the Rules tab.
3. Confirm there is a rule with:
   • Type: NTLM, and
   • Network definition: *Default

If that NTLM rule is present and correct, CyBlock is set up to identify users, and the problem is most likely on the Windows/browser side — continue to Step 2. If the rule is missing or its network definition is wrong, correcting it here is the fix.

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Step 2 — If employees are being prompted to log in (Windows/browser configuration)

What’s happening and why

CyBlock identifies users silently by asking the browser to confirm the employee’s Windows login as traffic passes through the proxy — normally invisible to the user. Recent Windows 11 and Edge/Chrome security changes tightened the rules around this automatic sign-in, so the browser now needs to be explicitly told it’s safe to release Windows credentials to the CyBlock proxy. If it isn’t, the browser either prompts the employee for credentials or skips identification entirely (leaving usernames blank).

This is a Microsoft security change, not a CyBlock defect. The fix is applied by your IT administrator via Group Policy (GPO), which pushes the settings to all computers at once. Getting cloud-proxy NTLM working reliably requires two GPO controls — both must be in place.

Which browsers need configuration

• Microsoft Edge — requires configuration
• Google Chrome — requires configuration
• Internet Explorer — not affected
• Firefox — uses a separate process; contact Wavecrest Support if Firefox is in use

Layer 1 — Allow the proxy to request Windows authentication (AuthServerAllowlist)

This tells Edge and Chrome that the CyBlock proxy is allowed to request integrated Windows authentication.

Microsoft Edge (GPO):

1. Open Group Policy Management Console (gpmc.msc) and edit a GPO linked to the OU containing your computers.
2. Go to Computer Configuration → Administrative Templates → Microsoft Edge → HTTP authentication.
3. Open Configure list of allowed authentication servers, set it to Enabled.
4. In the value field, enter: *.cloud.cyblock.com,cloud.cyblock.com
5. Click OK.

(First-time setup: download the Edge policy templates from https://www.microsoft.com/en-us/edge/business/download and copy msedge.admx / msedge.adml into your domain controller’s Central Store.)

Google Chrome (GPO):

1. In the same or a linked GPO, go to Computer Configuration → Administrative Templates → Google → Google Chrome → HTTP authentication.
2. Open Authentication server allowlist, set it to Enabled.
3. In the value field, enter: *.cloud.cyblock.com,cloud.cyblock.com
4. Click OK.

(Registry equivalent, for non-domain machines — apply as a computer/HKLM policy:

• Edge: HKLM\SOFTWARE\Policies\Microsoft\Edge → AuthServerAllowlist (REG_SZ) = *.cloud.cyblock.com,cloud.cyblock.com
• Chrome: HKLM\SOFTWARE\Policies\Google\Chrome → AuthServerAllowlist (REG_SZ) = *.cloud.cyblock.com,cloud.cyblock.com)

Layer 2 — Move the proxy into the Local Intranet zone (Site to Zone Assignment)

Even with Layer 1 set, Windows checks the security zone of the proxy host before it will release credentials automatically. Because cloud.cyblock.com is an internet-hosted address, Windows treats it as the Internet zone, and Internet-zone hosts prompt the user instead of signing in silently. The proxy must be reassigned to the Local Intranet zone for automatic authentication to work.

GPO:

1. Go to Computer Configuration → Policies → Administrative Templates → Windows Components → Internet Explorer → Internet Control Panel → Security Page → Site to Zone Assignment List.
2. Set it to Enabled, then click Show and add:
   • Value name: cloud.cyblock.com
   • Value: 1 (1 = Local Intranet zone)
3. Click OK.

(Even though the GPO path says “Internet Explorer,” this zone list is also read by Edge and Chrome for the integrated Windows authentication credential decision.)

(On-premise / appliance deployments: substitute your own internal proxy hostname for cloud.cyblock.com. Whether the zone step is needed depends on whether your proxy hostname already resolves to the Local Intranet zone — contact Wavecrest Support if unsure.)

Single-machine test (before a full GPO rollout)

To confirm the two-layer fix on one affected machine before deploying via GPO, run these as Administrator, then fully restart the browser and check the CyBlock log for usernames:

reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\ZoneMap\Domains\cloud.cyblock.com" /v https /t REG_DWORD /d 1 /f

reg add "HKLM\SOFTWARE\Policies\Microsoft\Edge" /v AuthServerAllowlist /t REG_SZ /d "*.cloud.cyblock.com,cloud.cyblock.com" /f

Apply and verify

1. Run gpupdate /force on a test machine (or wait for Group Policy to refresh).
2. Fully restart the browser — these policies require a complete browser restart, not just a new tab.
3. Confirm the policy is active: open edge://policy (Edge) or chrome://policy (Chrome) and check that AuthServerAllowlist shows the correct value.
4. Browse to any external site, then check the CyBlock activity log for the username.
5. If it’s still not working, check Event Viewer → Applications and Services Logs → Microsoft → Windows → GroupPolicy for GPO application errors.

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Troubleshooting

Symptom	Likely cause	Action
Usernames blank, no NTLM rule found	CyBlock auth rule missing	Add/correct the NTLM rule (*Default) in Authentication Manager (Step 1)
Login prompts persist after GPO deployed	Browser not fully restarted	Close and reopen all browser windows
Usernames still blank after Layer 1	Proxy still in Internet zone	Apply the Layer 2 Site-to-Zone assignment
Policy not showing in edge://policy	Edge ADMX templates not installed	Install templates in the Central Store on your domain controller
Only some computers affected	GPO linked to wrong OU	Ensure the GPO is linked to the OU with computer accounts, not user accounts

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Additional notes

• Apply these as computer policies (HKEY_LOCAL_MACHINE), not user policies.
• Multiple proxy addresses can be listed, comma-separated, no spaces.
• This is part of Microsoft’s ongoing phase-out of older authentication methods; Wavecrest will update guidance as the rollout continues.
• For help, contact support@wavecrest.net.