Because Zimbra doesn't have a "Grace Buffer." The moment the zimbraMailQuota attribute is met, the LMTP (Local Mail Transfer Protocol) service returns a 552 5.2.2 Over Quota error to the sender. The mail doesn't "wait in line"—it bounces back to the sender instantly. At JIL, we see ₹2 Lakh ($2,170) B2B leads vanish because a user ignored the 90% warning for three weeks. If you’re at 100%, you aren't just "Full"—you’re invisible to the outside world.

Surprisingly, yes—until the Sent folder tries to save a copy. The "Send" action is just a push to the SMTP relay, but the "Save to Sent" action is a write-to-disk. If your disk is full, the mail goes out, but you lose the record of it. This creates a massive Compliance Gap for firms handling ₹1.2 Cr ($130,222) contracts. You think you sent the invoice, but your evidence is gone because the server couldn't find a single spare byte to store the MIME file.

Because of the Zimbra Trash Retention Policy. When you hit "Delete," the mail just moves from one folder to another. It’s still occupying the same zimbraItem space in the MariaDB. You must Empty Trash and then wait for the zmcompact or the automated mailbox purge cycle to run. If you’re in a panic, run zmprov ma user@domain.com zimbraMailQuota 0 to temporarily set it to "Unlimited" while you clean up. It’s a ₹0 emergency bypass that saves a ₹50,000 ($542) workday.

Yes. A 10MB PDF doesn't take 10MB of quota; it takes roughly 13.5MB due to Base64 Encoding. When binary files are wrapped in MIME for email, they swell by 30-40%. If you have 100MB of "Buffer" left and someone sends a 80MB attachment, you’re going to bounce. Most JIL users forget this "Encoding Tax." We recommend keeping a 15% safety margin at all times to account for the overhead of Lucence Indexing and metadata bloat.

Because the Quota only tracks the Message Store. It doesn't track your Lucene Search Indexes, Briefcase Versions, or Metadata. If you have a 50GB mailbox, the actual disk footprint might be 60GB. If the underlying Linux partition (/opt/zimbra) hits 100%, the entire server crashes, not just your account. This is a ₹0 hardware oversight that causes a ₹1.5 Lakh ($1,627) disaster recovery bill. Monitoring the "Physical" vs. "Logical" storage is the only way to stay online.

No. Shared items count against the Owner’s Quota. However, if you "Copy" a 1GB folder from a colleague to your account, you just ate 1GB of your own space. In 2026, we see companies burning through ₹25,000 ($271) of extra storage per month just because users are "Hoarding" duplicates instead of using the "Mount" feature. Use zmmailbox mcf to check your folder-level bloat before you start begging the admin for more space.