Thanks Keith. I downloaded Dependency Walker. In the top left window I've got SQLITEFCTS.DLL highlighted. The bottom panel shows Error: At least one required implicit or forwarded dependency was not found. Warning: At least one delay-load dependency module was not found. The middle left panel has a string of modules the first 5 of which are API-MS-WIN-CORE-APIQUERY-L1-1-0.DLL API-MS-WIN-CORE-APPCOMPAT-L1-1-0.DLL API-MS-WIN-CORE-APPCOMPAT-L1-1-1.DLL API-MS-WIN-CORE-APPINIT-L1-1-0.DLL API-MS-WIN-CORE-ATOMS-L1-1-0.DLL The first 90+ have errors all of which are "Error opening file. The system cannot find the file specified (2)." showing on the middle right. On the top right lower panel there are 2 listed under Function _sqlite3_sqliteFcts_init __CPPdebugHook. I tried calling sqlite3_load_function with the entry point parameter set to "_sqlite3_sqliteFcts_init" (i.e. underscore before sqliteFcts) and it's now working. It would therefore seem to be a name wrangling thing but I'd like to get shot of the anomaly if possible. Use of _cdecl before the sqlite3_sqliteFcts_init declaration doesn't remove it.