If you're getting an unknown error when uploading an Excel file, the file may contain unsupported formatting, special characters, extra sheets, or other structural issues. This article explains the most common causes and how to fix them before uploading again.
- Check for multiple sheets
- Clear unsupported formatting
- Check for special characters
- Check for formulas, hidden cells, or locked cells
- Check file encoding
- Try saving as CSV
- Check required fields and valid values
- Troubleshoot generic "Line 0" errors
- Still stuck?
- FAQ
Note: Follow these troubleshooting steps in order, starting with the most common causes.
Check for multiple sheets
In most cases, your file must contain only one sheet before you upload it. If your workbook includes multiple tabs at the bottom of the file, delete the extra sheets or move all required data onto a single sheet before uploading.
Note: Order Exports are an exception and may include multiple sheets.
To remove extra sheets:
- Right-click the sheet tab you want to delete at the bottom of the workbook.
- Select Delete.
- Repeat until only one sheet remains.
Clear unsupported formatting
This error often happens when the Excel file contains formatting that NuORDER can't process during upload. Unsupported formatting may include:
- Borders
- Cell colors or fill
- Conditional formatting
- Merged cells
- Special characters in cell values
Note: Unsupported formatting can also be introduced when data is copied and pasted from another spreadsheet or document.
This example shows an Excel file with unsupported formatting, such as borders and cell colors.
NuORDER requires a clean file with no unsupported formatting applied.
To clear all formatting:
On Mac
- Select all data on the sheet using Command + A.
- On the Home tab, select the eraser icon, Clear, on the right side of the ribbon.
- Select Clear Formats.
On Windows
- Select all data on the sheet using Ctrl + A.
- On the Home tab, select the eraser icon, Clear, in the Editing group on the right side of the ribbon.
- Select Clear Formats.
This removes borders, colors, and other formatting while keeping your data intact.
The following examples are shown in Excel for Windows.
Check for special characters
Even after you clear formatting, the file may still contain special characters in cell values that can cause upload errors. Review your data for anything outside standard letters, numbers, and basic punctuation, then remove or replace those characters.
Examples of special characters may include:
- Trademark symbol:
™ - Registered trademark symbol:
® - Bullet point:
• - Curly quotes:
“ ”and‘ ’ - Long dashes: en dash
–and em dash— - Non-standard symbols copied from other documents or spreadsheets
Check for formulas, hidden cells, or locked cells
Clearing formatting removes visual styling, but it doesn't remove formulas, hidden rows or columns, or locked cells. These can still cause upload errors after a file appears clean.
Convert formulas to plain values
If your file contains formulas, replace them with plain values before uploading.
- Select all data using Command + A on Mac or Ctrl + A on Windows.
- Copy the selection using Command + C on Mac or Ctrl + C on Windows.
- Right-click the selected area.
- Select Paste Special > Values Only.
This replaces formulas such as =VLOOKUP, =CONCAT, or =SUM with their displayed results.
Unhide rows and columns
Hidden rows or columns can interfere with the upload structure.
- Select all data using Command + A on Mac or Ctrl + A on Windows.
- Right-click any row number or column letter.
- Select Unhide.
- Remove any helper rows or columns you don't need in the final upload.
Remove locked cells or sheet protection
Protected sheets can also cause issues.
- Go to the Review tab.
- If Unprotect Sheet is available, select it.
- If Excel asks for a password that you don't have, rebuild the file in a new, unprotected sheet.
Check file encoding
If the file was created or edited in another system, it may be saved in a format or encoding that the upload doesn't expect.
Examples: Files exported from another platform, or files that were opened and re-saved by a script.
To make sure the file is saved in a format the upload can read:
- Re-save the file directly from Excel using File > Save As
- If you save as CSV, choose CSV UTF-8 (Comma delimited) instead of plain CSV, especially if the file contains accented characters or non-English text
Try saving as CSV
If the file still won't upload after you complete the earlier troubleshooting steps, save it as a CSV and try the upload again.
Also, if your file includes UPCs or other long numeric codes, format those columns as text before saving. Otherwise, Excel may convert them to scientific notation.
To format a column as text:
- Select the column.
- Right-click and select Format Cells.
- Select Text.
- Select OK.
Check required fields and valid values
Missing required fields or invalid values can also cause upload errors. If the file structure looks correct, review the data overview article for the type of file you're uploading. Make sure all required fields are included, the column headers are correct, and the values in each field use a supported format.
- Company data overview
- Buyer data overview for brands
- Inventory data overview
- Product data overview
- Price sheet overview
Troubleshoot generic "Line 0" errors
Some uploads fail with a generic error such as "Line 0" and don't identify a specific row or column. This usually points to a file structure problem rather than a single bad value.
Try these checks:
- Confirm that row 1 contains only column headers, with no blank rows, merged cells, or title text above the headers.
- Check for any completely blank row or column inside the data range.
- Review the first data row, usually row 2 (the first row after headers), and make sure required columns contain valid values with no extra spaces.
- Re-check the earlier steps in this article, especially for hidden characters, formulas, locked cells, or extra sheets.
- If the file still fails, stop resubmitting the same version and contact NuORDER support with the exact error message and the file you tried to upload.
Still stuck?
If your file still won't upload after trying the steps above, contact NuORDER support.
If you contact support, include:
- The exact error message
- The file you tried to upload
- Which row contains your column headers
- Whether you already tried clearing formatting or saving as CSV
FAQ
Q: Why am I getting an unknown error when I upload an Excel file?
A: This usually happens because the file contains unsupported formatting, extra sheets, special characters, formulas, hidden content, or other structural issues that the upload can't process.
Q: Does clearing formatting remove formulas or hidden rows?
A: No. Clearing formatting removes visual styling, but it doesn't remove formulas, hidden rows or columns, or sheet protection.
Q: What should I do if clearing formatting doesn't work?
A: Check for extra sheets, special characters, formulas, hidden rows or columns, and locked cells. If the issue continues, save the file as CSV and try again.
Q: What does a "Line 0" error mean?
A: A "Line 0" error usually means the file structure is invalid, such as an incorrect header row, a blank row inside the data range, or hidden content affecting the upload.