Error 91 occurring during iterations randomly - vba

Question

Interesting problem here. This line of code works through multiple iterations until it reaches a point where it throws an Run-time error 91 at me: "Object Variable or With block variable not set". This is occurring in a function designed to find a deal number. The entire program is an end of day email generation program that sends attachments to various different counter-parties. The error occurs on the ** line. For additional color, temp deal is not empty when execution is attempted. There doesn't appear to be any extraneous trailing or leading spaces either. Thanks in advance!
Function getPDFs(cFirm As Variant, iFirm As Variant, row_counter As Variant, reportsByFirm As Worksheet, trMaster As Worksheet, trSeparate As Variant, trName As Variant, reportDate As Variant) As String
dealCol = 1
Dim locationArray() As String
Dim DealArray() As String
cDes = "_vs._NY"
iDes = "_vs._IC"
filePath = "X:\Office\Confirm Drop File\"
dealNum = reportsByFirm.Cells(row_counter, dealCol)
FileType = ".pdf"
If InStr(1, dealNum, "-") > 0 Then
DealArray() = Split(dealNum, "-")
tempDeal = DealArray(LBound(DealArray))
Else
tempDeal = dealNum
End If
'Finds deal location in spread sheet for further detail to obtain file path
**trLocation = trMaster.Columns(2).Find(What:=tempDeal).Address
locationArray() = Split(trLocation, "$")
trRow = locationArray(UBound(locationArray))
'Formats client names for 20 characters and removes punctuation (".") in order to stay within convention of file naming
cFirmFormatted = Trim(Left(cFirm, 20))
iFirmFormatted = Trim(Left(iFirm, 20))
'Finds clearing method
clMethod = trMaster.Cells(trRow, 6).Value
Select Case clmethod
Case "Clport"
'Prevents naming convention issues with punctuations in the name
If InStr(1, cFirmFormatted, ".") > 0 Then
cFirmFormatted = Replace(cFirmFormatted, ".", "")
End If
getPDFs = filePath & cFirmFormatted & "\" & reportDate & "_" & dealNum & "_" & cFirmFormatted & cDes & FileType
Case "ICE"
If InStr(1, iFirmFormatted, ".") > 0 Then
iFirmFormatted = Replace(iFirmFormatted, ".", "")
End If
getPDFs = filePath & iFirmFormatted & "\" & reportDate & "_" & dealNum & "_" & iFirmFormatted & iDes & FileType
End Select
End Function

Answer 1

Your code assumes that trLocation is always found, if it isn't found then you will receive an error because you don't have a range to return the .Address property for.
Try testing the result first:
Dim testLocation As Excel.Range
Set testLocation = trMaster.Columns(2).Find(tempDeal)
If Not testLocation Is Nothing Then
trLocation = testLocation.Address
'// Rest of code here...
Else
MsgBox "Cannot find """ & tempDeal & """!"
Exit Function
End If