If you are doing data entry, you may get this error if the data in one of your records does not match the datatype for that field.

If you are entering a number (with or without decimals) please don't enter commas.

You will also get this error if you are in a custom view (Custom Views (Sorting and Filtering), but do not have the id column included in the view, and you attempt to click through a link to a record.