Troubleshooting

The common failure modes across server registration, the file service, provisioning and licensing — with the fix for each.

1. Server registration & connection

Symptom	Likely cause / fix
Test connection fails	The API key isn’t allowed from the WHMCS server’s IP, the port is wrong, or the TLS mode is mismatched. For a self-signed Plesk cert, switch TLS mode to Skip verification (self-signed); for a real cert, use Verify certificate (CA).
Add/edit server rejected	The host field is strictly validated as an FQDN or IP because it’s later embedded in the file-service installer that runs as root. Enter a clean hostname/IP with no scheme or path.
DNS or Databases tab misbehaves on an older box	The native REST endpoints need a recent Plesk (18.0.49+ for DNS, 18.0.69+ for databases). DNS falls back to the CLI-gateway automatically; for databases, update Plesk. The Plesk version shows on the server card.

Verify the key by hand

A quick authenticated probe from the WHMCS box confirms the token and reachability independent of the module:

curl -sk -H "X-API-Key: <token>" \
  https://<plesk-host>:8443/api/v2/server

2. File service, logs & backups

Symptom	Likely cause / fix
File manager or Logs empty or erroring	The file-service daemon isn’t set up or hasn’t been tested. Run the one-line installer (Installer in the server’s menu) on the box, run Test connection to capture the TLS pin, then enable the File manager native feature under Settings → Native Features.
“Back up now” seems to do nothing	Backups run in the background — the backup_runner cron picks the job up within 2 minutes and the Backups tab shows its progress. Admin/CLI dumps are server-owned and therefore invisible in Plesk’s customer Backup Manager — the module’s own Backups tab lists them, which needs the file-service daemon to be active.
Test connection to file service fails after an install	Confirm the firewall allows the WHMCS server’s address (each address it may connect from — IPv4 and IPv6 if dual-stack) on TCP 8447, and that the impulse-fileproxy systemd unit is running.
File service reports a certificate that doesn’t match	The daemon’s certificate changed since its pin was captured. Find out why before going further; reinstalling with Installer starts over with a fresh pin.
Download/export of a backup refused	Export is single-domain-only by design — a shared/server-wide dump can’t be exported because it would package co-tenant data. Restore instead, or create a per-domain dump.

New client-area code looks stale after an upload

If your PHP opcache doesn’t revalidate files (opcache.validate_timestamps=0), reset it or restart PHP-FPM for the pool that serves WHMCS, or the updated client-area code won’t run.

3. Provisioning & the client area

Symptom	Likely cause / fix
Order placed but nothing provisions	The subscription is created when WHMCS runs the module’s Create command (per the product’s auto-setup setting); a failed or interrupted create is retried by the provision cron (every 2 min). When Create fails, WHMCS shows the reason (for example, no capacity in region …). Confirm Core’s cron runner is firing, and that a tested Plesk server with capacity exists in the order’s region.
Active service missing its Plesk subscription	Run Repair account relations (Dashboard → Maintenance) — it adopts a matching Plesk subscription by domain and reports orphaned rows.
Customer sees another tenant’s domain/DB, or is missing their own add-on domain	How Plesk links a domain to its subscription can differ between Plesk builds. Treat a cross-tenant view as urgent: contact Impulse Software support with the Plesk version from the server card.
SSO lands on the panel home instead of the target screen	The sign-in worked; deep links into Plesk screens differ between Plesk versions and roles. Report the Plesk version to Impulse Software support.
A client-area tab shows “not included in your plan” unexpectedly	That tab needs both an active license and the plan’s feature flag. Check the plan’s feature flags and the Core license status.

4. Licensing

Symptom	Likely cause / fix
License badge reads the wrong tier	Confirm the key is entered in ImpulseCore → Modules & Licensing → Licenses for impulseplesk and validates against the signed endpoint. Check ImpulsePlesk → Diagnostics → License for the resolved status, tier and features.
License shows Invalid	Each check sends your WHMCS install’s domain (the System URL host), server IP and install path. A moved install surfaces as Invalid — update its domain under Change domain on the license in the Impulse Software portal (for a new server IP, contact support), then click Re-check now under ImpulseCore → Modules & Licensing → Licenses.
Dev caps hit unexpectedly	An IPLSKDEV- key is capped at 3 hosting services, 2 servers and 3 plans. Use an IPLSK- key for production volume.

Licensing is XML, cached with grace

ImpulseCore owns the parsing and caches the result with a grace window, so a transient licensing-server error won’t immediately break access. Persistent failures point at the key, the domain, or connectivity to the signed endpoint.

5. Still stuck?

Collect the module’s audit-log entries for the failing action (secrets are redacted) and the raw Plesk error kept operator-side, then contact Impulse Software support at support.impulsesoftware.com or [email protected]. Include the Plesk version reported on the server card, the TLS mode, and whether the file-service daemon is active.