where can i found the codeunit 10803 “Post Code Lookup” in the v4.01 Philippe
The number 108xx means that you are looking for a localised object. Do you have the french version of 4.01 or do you have the W1 database?
i have the french version of the 4.01
If the Codeunit 10803 Post Code Lookup was present in FR2.60 and is no longer present in FR4.0 SP1, then maybe the French team which localizes Navision decided the existing W1 functionality is now enough for French post codes. There is a big difference in how post codes are handled between 2.60 and 4.0.