Troubleshooting: failed or odd schedule imports

The import fails outright

• “No tasks were found in this file” — the file is empty, it's the wrong sheet, or the task name column isn't recognised. In Excel, put the task list on the first sheet with a header row (Name, Duration, Start, Predecessors).
• .mpp file rejected — save from Microsoft Project as XML (File → Save As → XML Format) and import that.
• P6 export rejected — export as XER (or P6 XML), not PDF or Excel layout.
• File too large or times out — split very large programs by project, or remove resource and cost tables before exporting.

Warnings in the preview and what they mean

• “N link(s) pointed at missing tasks… were skipped” — the predecessor was outside the exported range or filtered out. Re-export with all tasks, or add the links after import.
• “link(s) to other projects were skipped” (P6) — cross-project links can't come across. Add a milestone for the outside date and link to that.
• “Percent lag … converted to 0 days” (Microsoft Project) — lag stated as a % isn't supported. Fix the lag in the preview or after import.
• “Level-of-effort/WBS summary … imported as a regular task” (P6) — check its duration after import or delete it.
• “predecessor reference(s) didn't match a task” (Excel/CSV) — predecessors must be row numbers or IDs from the same file, like 3, 3FS+2 or 3SS.
• “Columns not imported: …” — those columns aren't mapped. Rename them to Name, Duration, Start, Finish, Predecessors, Trade or Notes.
• “row(s) had formatting problems” — usually a stray quote or line break inside a cell. Save as CSV UTF-8 and try again.
• “The file has several projects; importing …” — only the first project is imported. Export one project per file.

Dates look shifted

• Your work calendar differs from the source. Construction Company Software recalculates with the project's calendar — if the source worked Saturdays, set up a 6-day calendar in Settings → Work calendars before importing.
• Day and month swapped (03/04 read as March 4 instead of 3 April): use YYYY-MM-DD dates in Excel or set your sheet's date format before saving as CSV.
• Tasks all start on the project start date: there were no links in the file. Leave start dates in, or add links after import.
• Constraints from the source (must start on, start no earlier than) are kept and can pin tasks. Check the constraint column on tasks that won't move.

Durations look wrong

• Durations are working days. “2w” is read as 10 days, and durations stored in hours are converted to working days.
• Milestones must have 0 duration — anything with a duration imports as a task.

Undo a bad import

Every import is saved as a schedule change. Open Baselines & versions and restore the version from before the import, or delete the imported tasks and import again. Deleted tasks can also be restored from Settings → Recycle bin for 30 days.