Hello everyone:I have been working with the SDK in the P6 version 8.3, and I interacted without problems between the database and the SDK spreadsheets. After to upgrade to version 8.3.15 the spreadsheet Activity6v6.xls works partially: every time I try "Set Activity Relationships", I get the following error: "Row 3: Insert new TASKPRED: Values are required for lag_hr_cnt" for each of the activities that the project has. I have verified with previous projects where I have entered this information without problems and it gives me the same result, so I conclude that it is due to the upgrade made. Does anyone have any ideas? Thanks alexander