Yup, I'm getting that same error too. Open P2K Commander (4.9.A), it connects fine to my phone (V3xx, Cingular), but then when I click "Seem -> Functions" I get the "functions excel file not found" error message. I assume it's looking for the "SeemFunctionsP2k.csv" file, but It's looking under the wrong name. Anyone know the correct filename that it's looking for?
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Ha, I answered my own question. After a bit of trial and error, I've discovered that P2KCommander is looking for the filename "Functions.csv", so just rename your "SeemFunctionsP2k.csv" file to "Functions.csv".
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One more thing, the "SeemFunctionsP2k.csv" file does not have any of the latest seems for p2k05 phones, so If you have a P2K05 phone (V3xx or Maxx V6), a master list of hacks is here:
http://xlr8.us/hofo/map_p2k05.txt (stole this info from xlr8.us/hofo/)