Event editor error APP999 — "longer than 1500 bytes" (description too long to save)

APP999 is a generic code — it appears on several unrelated errors, not just this one. This article covers the specific message "The value of property '<field>' is longer than <N> bytes." If your APP999 message reads differently, this article may not apply — contact support with the full text instead.

What this error means

Every text field on an Event/Activity (most often the description, per language) has a maximum saved size of 1500 bytes. That limit is measured on the saved text — including any bold, links, lists or other formatting — not on how many characters you see on screen. Two descriptions that look about the same length can behave differently if one carries more hidden formatting than the other.

A full example looks like:

The value of property "description" is longer than 1500 bytes. (app999)

Why it happens

• Formatting adds hidden size. Bold, italics, links and lists are all stored as extra markup around your text, so a heavily formatted description can hit the limit well before 1500 visible characters.
• Pasting can carry more than you expect. Copying text from another event, a Word document, or a webpage often brings invisible formatting along with it — sometimes more than the original had, and it can differ between one paste and the next even when the visible text looks identical. This is why copy-pasting the same-looking text into a second event can fail even though it worked for the first.

What to do

1. Keep descriptions well under 1500 bytes. As a rough guide, aim for noticeably fewer than 1500 characters if you're using any bold, links or lists — formatting eats into that budget.
2. Paste as plain text where you can (in most browsers, Ctrl/Cmd+Shift+V) rather than a direct paste, especially when copying from another event, a document, or a webpage — it strips the hidden formatting that inflates the saved size.
3. If you're editing multiple languages at once, save one at a time. That makes it obvious which language's description is the one over the limit.
4. If you hit this error, go back and double-check the rest of that event — dates, pricing, and any other language's description you edited in the same session. An oversized description can currently stop the whole save partway through, so other changes you made at the same time may not have saved either, even though only the description triggered the error.

When to get in touch

Contact support if:

• You've trimmed the description well below 1500 characters, pasted as plain text, and it's still being rejected.
• You're not sure whether other fields on the event (dates, pricing, other languages) saved correctly after hitting this error.
• The message text doesn't match the "longer than N bytes" wording above.

We're aware this error can be more disruptive than it should be, and it's on our list to make safer.

Still stuck?

Contact support with the event/activity name, your store name, and the full error message — that's enough for us to trace exactly what happened.