I have theories as to why this is occurring but, for now, here is what happened. One of the sheet formulas looks something like this:
=IF([COLUMN A]1 = "YES", INDEX({Smartsheet 1 Column B}, MATCH([PROJECT#]1, {Smartsheet 1 Column A}, 0)), IF([COLUMN A]1 = "NO", INDEX({Smartsheet 2 Column B}, MATCH([PROJECT#]1, {Smartsheet 2 Column A}, 0))))
In other words, if YES > go to Smartsheet A and get data. If NO > go to Smartsheet B and get data.
On Friday January 24th, the formula worked, no errors. However, on Monday January 27th the formula result displays a #CIRCULAR REFERENCE error. The first IF statement pulls data from Sheet 1 but when I remove the first IF statement and only search for the NO results in Sheet 2, I still get the #CIRCULAR REFERENCE error.
On Monday, how did I fix the #CIRCULAR REFERENCE error? I copied and removed the formula in one cell. Then I paste the formula (exact same formula). Save, then all column data is restored. I did not change or update any cross-sheet formulas.
The problem is that we track changes. All the columns that are affected by the random error appear as updated or new entries.
Today is Tuesday January 28th and there are no errors, the formula works. I am sure next Monday, the #CIRCULAR REFERENCE error will appear again (fingers crossed it will never happen again). Is there a weekend or biweekly system refresh that could be removing cross-sheet references? This is a mystery to me, but it has happened a few times over the past few months. I receive emails from frustrated data entry personnel because the referenced data is missing.
When it happens again, I will add a new comment to this Community discussion.
Thank you.