--- title: "Troubleshooting overview" description: "How to diagnose problems fast — pick your symptom, follow the checks in order, and know what to include when you escalate." type: "troubleshooting" audience: [network-manager, publisher, advertiser, admin] keywords: [troubleshooting, symptom, diagnose, not serving, empty ad, discrepancy, faq] --- Fetch the complete documentation index at: https://epom.com/ad-server/docs/llms.txt. Use this file to discover all available pages before exploring further. Append .md to any documentation page URL to get its markdown version. # Troubleshooting overview This section is organized by **symptom**, not by feature. Find the line below that sounds like your problem, open the page, and work through the checks **in the order given** — each list is sorted from the most common cause to the rarest, and from things you can verify yourself to things that need your network administrator or Epom support. ## Before you start Three habits that shorten every investigation: 1. **Note what changed last.** Most breakage follows an edit — a resized banner, a tightened targeting rule, a new limit. The account keeps a **Recent** history of the pages you opened (clock icon in the top bar), and `GET /rest-api/action-log/mine.do` (or the assistant's `recent_changes`) lists your own recent changes. 2. **Trust the built-in signals over your memory.** Banner and placement edit pages carry a serving-state pill (red *Not serving* / yellow *Rules only* / gray *Paused* / green *Serving*), approval badges, and — for roles that hold the matching permission — *Matched banners* / *Matched placements* cards that show what the ad server's snapshot actually matched. Start there instead of re-checking settings one by one. 3. **Separate "no ad" from "no numbers".** An empty slot on a page and a low figure in a report are different problems with different check lists. If the ad visibly serves but the totals look wrong, go straight to [Analytics discrepancies](https://epom.com/ad-server/docs/troubleshooting/analytics-discrepancies.md). ## Symptom index | Symptom | Go to | |---|---| | The ad slot is empty, or the passback/default ad shows instead of my campaign | [My ad is not serving](https://epom.com/ad-server/docs/troubleshooting/ad-not-serving.md) | | A specific banner never appears even though others on the placement do | [My ad is not serving](https://epom.com/ad-server/docs/troubleshooting/ad-not-serving.md) | | A PMP private deal wins nothing, or far less than agreed | [My PMP deal is not delivering](https://epom.com/ad-server/docs/troubleshooting/pmp-deal-not-delivering.md) | | Requests come in but only some turn into impressions — inventory is going unfilled | [My fill rate is low](https://epom.com/ad-server/docs/troubleshooting/low-fill-rate.md) | | Requests and Fill Rate columns vanished from my report | [My fill rate is low](https://epom.com/ad-server/docs/troubleshooting/low-fill-rate.md) | | The tag is on the page but nothing renders at all — not even a passback | [Tags and preview problems](https://epom.com/ad-server/docs/troubleshooting/tags-and-preview.md) | | Preview shows the ad, the real page doesn't (or the reverse) | [Tags and preview problems](https://epom.com/ad-server/docs/troubleshooting/tags-and-preview.md) | | There is no Preview button on my placement or banner | [Tags and preview problems](https://epom.com/ad-server/docs/troubleshooting/tags-and-preview.md) | | A Google Ad Manager passback shows once, then the placement reloads into a blank slot | [Google (GPT) passback tags in a placement](https://epom.com/ad-server/docs/troubleshooting/google-passback-tags.md) | | Google returns no ad and the request is lost instead of falling back | [Google (GPT) passback tags in a placement](https://epom.com/ad-server/docs/troubleshooting/google-passback-tags.md) | | A video ad won't play, the player skips content, or I got a VAST error code | [Diagnose video ad playback failures (VAST errors)](https://epom.com/ad-server/docs/troubleshooting/vast-errors-and-playback.md) | | Clicks aren't counting, or impressions double-count, on a third-party HTML/JS tag | [Fix click tracking on third-party ad tags](https://epom.com/ad-server/docs/troubleshooting/click-tracking-third-party-tags.md) | | My numbers don't match a partner's / a third-party ad server's | [Analytics discrepancies](https://epom.com/ad-server/docs/troubleshooting/analytics-discrepancies.md) | | The dashboard and a report disagree, or yesterday's numbers changed today | [Analytics discrepancies](https://epom.com/ad-server/docs/troubleshooting/analytics-discrepancies.md) | | A page, card, button or dropdown option is missing or greyed out | [FAQ](https://epom.com/ad-server/docs/troubleshooting/faq.md) — permissions and shares answers | | An entity is shown in *italics*, or its form is locked | [FAQ](https://epom.com/ad-server/docs/troubleshooting/faq.md) | | A banner turned itself off, or got unlinked from placements | [FAQ](https://epom.com/ad-server/docs/troubleshooting/faq.md) | | I deleted an advertiser, campaign, banner, site, zone or placement by mistake | [Restore something you deleted by accident](https://epom.com/ad-server/docs/troubleshooting/restore-deleted.md) | | Demo account questions (expiry, locked overlay, See live) | [FAQ](https://epom.com/ad-server/docs/troubleshooting/faq.md) and [Demo accounts](https://epom.com/ad-server/docs/roles/demo-account.md) | ## When you escalate If the checks do not resolve it, ask your network manager or Epom support or your account manager — [Contact Epom support](https://epom.com/ad-server/docs/troubleshooting/contact-support.md) says who handles what — with: - the **entity IDs** involved — placement, banner, campaign (the ID is part of the edit page address, and **Account → Preferences → Show entities' IDs** shows them beside names); - the **time window** when you observed the problem, and your reporting time zone; - what the **serving pill and Matched cards** showed on the entities involved; - for tag problems: the page URL where the tag is embedded and which tag type you used; - for analytics problems: the report type, filters, and the two numbers being compared. Your network administrator can additionally check gates that account users cannot see — consent enforcement, bot and IP filtering, DSP creative-scan verdicts — and Epom support the ad-server snapshot state. The checks that need either are marked as such on each page. ## Related - [Contact Epom support](https://epom.com/ad-server/docs/troubleshooting/contact-support.md) - [My ad is not serving](https://epom.com/ad-server/docs/troubleshooting/ad-not-serving.md) - [My fill rate is low](https://epom.com/ad-server/docs/troubleshooting/low-fill-rate.md) - [Tags and preview problems](https://epom.com/ad-server/docs/troubleshooting/tags-and-preview.md) - [Google (GPT) passback tags in a placement](https://epom.com/ad-server/docs/troubleshooting/google-passback-tags.md) - [Diagnose video ad playback failures (VAST errors)](https://epom.com/ad-server/docs/troubleshooting/vast-errors-and-playback.md) - [Analytics discrepancies](https://epom.com/ad-server/docs/troubleshooting/analytics-discrepancies.md) - [FAQ](https://epom.com/ad-server/docs/troubleshooting/faq.md) - [Restore something you deleted by accident](https://epom.com/ad-server/docs/troubleshooting/restore-deleted.md) - [How ad selection works](https://epom.com/ad-server/docs/concepts/how-ad-selection-works.md) - [Serving state](https://epom.com/ad-server/docs/concepts/serving-state.md)