> For the complete documentation index, see [llms.txt](https://docs.zephyrintel.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zephyrintel.com/documents/troubleshooting-uploads-and-downloads.md).

# Troubleshooting uploads and downloads

Reference for the messages you may see while uploading, downloading or previewing documents.

### Messages and what to do

| Message                                                                               | When it appears                                                       | What to do                                                                     |
| ------------------------------------------------------------------------------------- | --------------------------------------------------------------------- | ------------------------------------------------------------------------------ |
| Too many files. Maximum 50 per batch.                                                 | You selected more than 50 files in one upload                         | Upload the files in smaller batches                                            |
| Unauthorized. Please sign in again.                                                   | Your session expired during upload; the rest of the batch stops       | Sign in again and retry                                                        |
| Forbidden. You do not have upload permission.                                         | Your account cannot upload documents                                  | Ask your administrator for upload access                                       |
| File is too large.                                                                    | The file exceeds the size the server accepts                          | Use a smaller file, or split it into parts                                     |
| Unsupported file type.                                                                | The file extension is not one Signal accepts                          | Convert the file to PDF, DOC, DOCX, XLS, XLSX, CSV, JPG, JPEG, PNG, GIF or SVG |
| Cancelled                                                                             | The upload was stopped before it finished                             | Click **Retry** on the file's card                                             |
| Upload failed                                                                         | A different upload problem occurred                                   | Click **Retry**, or check your connection and try again                        |
| Select a customer from the dropdown for each file, or clear the customer field.       | You typed customer text that does not match an existing customer      | Choose a customer from the dropdown, or clear the field                        |
| Select serial numbers from existing options for each file, or clear the serial input. | You typed a serial number that is not in Signal                       | Choose a serial from the suggestions, or remove it                             |
| Remove serial numbers that do not belong to the selected customer for each file.      | A chosen serial belongs to a different customer than the one selected | Remove the mismatched serial or change the customer                            |
| Pop-up blocked. Allow pop-ups and try again.                                          | Your browser blocked **Open in new tab**                              | Allow pop-ups for Signal and try again                                         |
| Unable to open PDF preview.                                                           | The PDF could not load in the inline viewer                           | Try again, or use **Download instead**                                         |
| Unable to download document.                                                          | The file could not be downloaded                                      | Try again, or check your connection                                            |
| Unable to open document.                                                              | The file could not be opened in a new tab                             | Try again, or use **Download** instead                                         |