> For the complete documentation index, see [llms.txt](https://knowledge.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://knowledge.illumina.com/microarray/general/microarray-general-troubleshooting-list/000003031.md).
# How to Troubleshoot the GenomeStudio Genotyping Error "Error writing data beyond end of sample"
#### **Description of Error**
During the final step of creating a GenomeStudio Genotyping project, a pop-up window may appear displaying the error message: "Error - writing data beyond end of sample" (Figure 1).
**Figure 1.** Pop-up window in GenomeStudio displaying the error message: "Error - writing data beyond end of sample."
The error is followed by a second pop-up window displaying the message: "The Project can not be created. No valid samples were loaded." (Figure 2). As a result, GenomeStudio is unable to create a project.
**Figure 2.** GenomeStudio pop-up window displaying the error: "The Project can not be created. No valid samples were loaded."
####
#### **Resolution**
* This error can occur when both IDAT (intensity data files) and GTC (genotyping call files) files are located in the same repository folder.
* To resolve the issue, move the GTC files to a separate folder, ensuring that only the IDATs remain in the scan folder.
* When recreating the project, GenomeStudio should be able to access only a single source file type (IDAT files).
**Reference:**
* [Can Genotype Call (GTC) files be used as input for GenomeStudio?](/microarray/general/microarray-general-reference_material-list/000005917.md)
\
\
\
| |
| :---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: |
| *For any feedback or questions regarding this article (Illumina Knowledge Article #3031), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000005917%20-%20Microarray%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://knowledge.illumina.com/microarray/general/microarray-general-troubleshooting-list/000003031.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.