For those who are utilising the fantastic world of Google Docs, you will be aware of some of the limitations that counteract the many advantages. One is the difficulty with external links, and in particular, keeping those external links working!
If you find that your IMPORTRANGE links to other sheets are not working, then you can force the formula to recalculate via slight variations by combining IF and ISERROR into the following formula:
=IF(ISERROR(ImportRange(SpreadSheet_GUID,”Sheet!p:P”)),IF(ISERROR(ImportRange(SpreadSheet_GUID,”Sheet!P:p”)),ImportRange(SpreadSheet_GUID,”Sheet!P:P”),ImportRange(SpreadSheet_GUID,”Sheet!P:p”)),ImportRange(SpreadSheet_GUID,”Sheet!p:P”))
You can also add in a RangeName from the external reference for an extra variation.