The error code 0x800A03EC
(or -2146827284) means NAME_NOT_FOUND; in other words, you've asked for something, and Excel can't find it.
This is a generic code, which can apply to lots of things it can't find e.g. using properties which aren't valid at that time like PivotItem.SourceNameStandard
throws this when a PivotItem doesn't have a filter applied. Worksheets["BLAHBLAH"]
throws this, when the sheet doesn't exist etc. In general, you are asking for something with a specific name and it doesn't exist. As for why, that will taking some digging on your part.
Check your sheet definitely does have the Range you are asking for, or that the .CellName
is definitely giving back the name of the range you are asking for.