VBA Code for Vlookup between two open workbooks

[EXCELISFUN1]

I am looking for VBA code to enter vlookupformulas in columns AS through AX (lookup data in column A - varying rowlengths each month). The lookup data will be in another open workbook (prior month (different filename each month: YYYY-MM Project Level (QuickCheck)in columns X through AC. There are 4 tabs in the 'prior month'workbook named the same each month (ORG1, ORG2, ORG3 & ORG4).

I run four separate ORG reports each month and the vlookupformula needs to be pointed to the same ORG tab in the prior month workbook.
For clarification: I run and download into Excel ORG1, thevlookup formula needs to use the prior month file, ORG1 tab to return thevalues.
I have searched and searched and can find VBA that does someof it, but I'm a newbie at VBA and am having a hard time with the two differentworkbooks (even though both are open) and the how to handle the variable tabnames.

Thanks for any assistance. I've been working on this for twodays. I have all of the other pieces that I need; I'm just stuck on this one.

Wanda
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