What Causes The Issue?

This problem is usually caused by the Custom Column being too long, or the Campaign name being too long. The platform has an in-built limitation of 1024 characters for Custom Columns. Our Product team is actively working on increasing this limit, but in the meantime you can follow the workaround outlined below to successfully upload your new Custom Column(s).

How To Fix The Issue

If you're seeing this error due to a Campaign name that is too long, please shorten your campaign name.

The workaround outlined below works by splitting a Custom Column into two, then adding them together. This ensures that the field never exceeds the 1024 character limit.

To upload your Custom Column, follow these steps:

1. Split your Custom Column definition logically so that it doesn’t exceed the 1024 limit. Splitting in two is usually sufficient.
2. Add the first half of the definition to a new Custom Column called Custom1 (or anything you like).
3. Add the second half of the definition to a new Custom Column called Custom2 (or anything you like).
4. In your original Custom Column field, use the definition [Custom1] + [Custom2]. This avoids the character limitation and will allow you to upload the required Custom Column successfully.