Trace error.

Trace Error Values

If you want to find answer to question - why this cell produces error value, this command will help you. Trace error command will analyse all precedents of formula in-depth. And only cells, which are at the beginning of the error chain, will be filtered and shown. So, you will see only sources of error, not a long chain with errors, which could contain more than 1000 levels on a large spreadsheet.

Note  To analyse why cell contains error use Evaluate cell command in context menu. It will show values of each sub-expression in formula. You should only find which of them conta