Your sales team opened a new deal yesterday. One person updated it in Affinity. Another replied to the prospect's last email—but the reply never landed in the CRM. By the time you noticed, the thread had drifted for six hours. The deal context is now fragmented across Gmail and your relationship database, and nobody has a complete picture of what was promised. Affinity's email sync is fast and usually silent. When it breaks, the silence is the worst part. You don't get a notification that integration has failed—you discover it three deals later when someone asks, "Where's the last message from the buyer?" and the answer is: nowhere in your CRM. This guide walks you through the three most common failure modes, a reset checklist you can execute in 30 minutes, and how to recover emails that fell through the gap. Why Affinity email sync fails: three root causes 1. API permission drift or account lock Affinity connects to Gmail and Outlook via OAuth tokens. These tokens expire, get revoked, or get locked down by security policies you didn't know your organization had. Common triggers: Password change without re-authorization. You changed your Gmail or Outlook password. The token is now invalid, but Affinity doesn't immediately alert you—it just silently fails on the next sync attempt. Two-factor authentication (2FA) turned on or changed. If you upgrade your security posture mid-year, your OAuth connection breaks until you re-authorize. Corporate account lock or IP restriction. Your IT team added conditional access rules or flagged unusual login activity. Affinity's sync servers can't authenticate even if your personal credentials work. Account suspension or recovery mode. Google or Microsoft detected unusual activity and locked the account pending verification. Affinity can't sync until you're back in. 2. Quota exhaustion or API rate limits Gmail and Outlook both rate-limit API calls. If Affinity hits those limits (which happens faster than you'd think on accounts with high email volume), the sync queues and either catches up later or fails silently. This is especially common if: You're syncing multiple Affinity users to the same Gmail account (a common setup for shared inboxes). You've integrated Affinity with other tools that also call Gmail API (Slack, Zapier, etc.). Your email account has thousands of active contacts or threads, and Affinity is re-indexing. 3. Affinity platform outage or sync service degradation Affinity's sync service goes down occasionally. Unlike a hard outage, degradation is worse—partial sync happens, some emails land, others don't, and you won't know which. Check Affinity's status page before you start troubleshooting. If there's a known issue, you're waiting, not diagnosing. Diagnose the break in five steps Step 1: Check the sync timestamp Open Affinity and navigate to Settings > Email Sync . Look at the "Last synced" timestamp for each email account. If it's fresh (within the last hour), skip to step 3. If it's stale (more than 6 hours), note the time. That's your failure window. Step 2: Test credential re-entry Go to your Gmail or Outlook account settings and check: Is 2FA active? If yes, was it recently changed? When did you last change your password? Are there any security alerts in your account activity log? If using a corporate account, did your IT team recently update conditional access policies or IP allowlists? If any of these changed in the last few weeks, the sync token is likely stale. Step 3: Disconnect and reconnect In Affinity, click Disconnect on the broken email account. Wait 30 seconds, then click Reconnect and re-authorize through OAuth. This forces a fresh token. It takes 90 seconds and fixes 70% of sync failures. Step 4: Check email forwarding and filters In your email provider, verify that: No rules or filters are automatically archiving, deleting, or forwarding emails without your knowledge. Email forwarding is not enabled. If you're forwarding mail elsewhere, Affinity may not see the original messages. Labels or inbox filtering rules aren't excluding the messages Affinity needs to sync. Step 5: Check for rate limiting In your email provider's activity or security log, look for: Gmail: Settings > Security > Your Google Account activity. Look for blocked sign-in attempts from Affinity's IP ranges. Outlook: Account.microsoft.com > Security > Recent activity. Look for "unusual activity" blocks. If you see blocks, your IT team may have flagged the integration. Reach out to them to whitelist Affinity's API servers. The reset checklist: 30-minute fix If reconnecting didn't work, follow this sequence: Disable any third-party email integrations temporarily. If you have Zapier, Make, or other tools syncing to the same Gmail/Outlook account, pause them for 10 minutes. Test if Affinity syncs without them. If it does, you have an API quota conflict. Clear your browser cache and cookies. Log out of Affinity completely. Clear cookies for affinity.co. Log back i