Ignore File Name / Save File Name Different If Other Exists?

My macro pulls data from a set of files in a folder and creates an output based on my formatting rules.

Ran into 2 issues though. The first being is after this macro is run it saves a file in the folder with the name "Data Export" and before I had it do this if "Data Export" was already there

Code:
'Check if file name to save exists If Dir$(vFolder & "" & sSubFolder & ".xls", vbNormal) = "" Then
wb.SaveAs vFolder & "" & sSubFolder & ".xls"
MsgBox "Complete!", vbOKOnly
Else
MsgBox "File already exists, could not save!", vbInformation, "COMPLETE!"
End If

What I want it to do instead is change itself and save it as Data Export A, and then also loop for A each time, if A is there go to B , so on and so forth.

-Alternate solution if this is way to challenging, can I have it pop up the Save Message box to let the user try a new name if "Data Export" exists. I was trying to think through that too..

2nd Issue is when I loop the files in the folder I selected in my macro, I want it to ignore "Data Export" files. Before I just took a shortcut and had it save outside of the data folder, which was fine but now we are running on so many files a day that we need it inside the same folder for organization purposes.

That is done with the following

Code:
'Loop through files in folder sFileName = Dir$(vFolder & "")
Do Until sFileName = ""

I was thinking maybe I can add an error handler to the loop? Before Do Until? Something like this? But how I can add it into the loop?

Code:
If sFileName Like "????.?.xls" Then