Reference Number

Hello again, it's been a while.

I am currently creating a spreadsheet to record incoming files for my company. Each file must have a unique reference. Part of this reference will be made up of the file name and client name.

At present I have the following formula:

=LEFT(B4,1)&MID(B4,1,1)&LEFT(C4,1)&"_0001"

Which produces something similar to BBG_0001

Although this is a fairly unique reference already I need 0001 to be a unique number in its own right. This can be in any format provided it is a number and it has a minimum of 4 digits. It would be preferable for it to be in sequence but not essential.

It should be noted that once these files have been dealt with the row containing the information (including reference) will be cut from that sheet and pasted into another sheet.

Any help apriciated.

Any questions please ask.

Thank you