A file that imports cleanly can fail after you edit and resave it because the line ending characters at the ends of rows were changed or dropped during the save. The Import Export PowerTool relies on proper carriage return and line feed terminators to recognize where each row ends, and some save paths do not preserve them. The fix is to save the file in a way that keeps correct line terminators and to verify them before importing.
Why line endings matter
The tool reads tab separated text files in which every row ends with a carriage return and line feed pair. When those terminators are present, the tool can separate one record from the next. When they are missing or replaced with a single character, the import can fail with confusing messages such as a table or field that cannot be found, even though the data itself looks correct. The line ending is invisible in most editors, which is why this problem is easy to overlook.
Saving from Excel the right way
When you save a worksheet from Excel on Windows using the tab delimited text option, Excel writes carriage return and line feed pairs and produces a file the tool can import. The behavior can differ on Excel for Mac, where saved text files may use a different line terminator. If you work on a Mac and an import fails, that platform difference is a likely cause. A dependable workaround on any platform is to copy the data from Excel and paste it into a plain text editor, then save from there.
Verifying line endings and encoding
A good text editor such as Notepad plus plus or TextPad lets you reveal the normally invisible formatting characters so you can confirm that each row ends with the expected terminator. If you do not see a line feed character at the end of a line, the file will probably not import. These editors also show the text encoding. Set or confirm the encoding as UTF 8, which is Unicode and handles international and special characters correctly on both export and import. A file saved in an older character set can also trigger import errors, so checking encoding at the same time as line endings resolves many failures at once.
A reliable editing workflow
Many practitioners keep their working file as an Excel workbook so that formulas and formatting are preserved, then copy the finished data and paste it into a plain text editor before saving as text for import. This keeps the convenience of Excel for editing while ensuring the imported file has correct terminators and encoding. There is no need to manually adjust files in a hex editor when you follow this approach.
Related Tools
Import Export PowerTool is the Insight Works app that imports and exports Microsoft Dynamics 365 Business Central data using tab separated text files. Because it depends on correct line terminators and encoding, verifying those two things in a text editor prevents most import failures.
Missing line endings are a formatting issue, not a limitation of the tool. Save your file as tab delimited text, or copy and paste from Excel into a text editor, confirm the line terminators and UTF 8 encoding, and your import will run as expected.