# GPT function issues (GPT for Excel – Autosheet)

## Invalid name

`#NAME? Invalid Name Error. The formula contains unrecognized text.`

![](https://autosheet.com/docs/article-images/help/invalid-name-error-excel.png)

**Problem**: GPT functions are not recognized by Excel.

> **Solutions**
>
> - [Check that GPT for Excel – Autosheet is installed](https://autosheet.com/docs/gpt-for-excel/setup/install) on your current Microsoft account.
>
> - On the [ribbon](https://support.microsoft.com/en-US/Office/foundations-experiences/show-or-hide-the-ribbon-in-office), select **Home > GPT for Excel Word – Autosheet** to enable the GPT functions.
>
> - If the problem persists, try activating the add-in (the experience might be slightly different for Mac users):
>
>   1. On the ribbon, select **Home > Add-ins > More Add-ins**. The **Office Add-ins** dialog opens.
>   2. Select the **My Add-ins** tab.
>   3. Select **GPT for Excel Word – Autosheet** and click **Add**.
>   4. On the ribbon, select **Home > GPT for Excel Word – Autosheet**.
>   5. In the sidebar, select **GPT functions**.
>   6. Click **Retry errors**.
>
> - Use the add-in in Excel for the web (see [supported versions](https://autosheet.com/docs/gpt-for-excel/troubleshooting/installation-issues#add-in-not-supported)).

## Invalid parameter

`Error: Invalid xxx parameter.`

**Problem**: The error indicates a formatting issue or an unreadable parameter within the formula.

> **Solutions**
>
> - Check that your parameters are in the correct order. [See the function list.](https://autosheet.com/docs/gpt-for-excel/gpt-functions/reference)
>
> - Check that all parameters (even optional ones) are added as empty when there is another parameter coming after them:
>
>   ✅ `GPT_TRANSLATE(A2, "french", , "Avoid passive voice")`
>
> - Check that you are using the right parameter separator for your locale: `,` or `;`
>
> - Check that you are using the correct number formats for temperature for your locale: `0.8` or `0,8`

## Missing parameter

`#ERROR: Missing required arguments categories for function GPT_XXX.`

**Problem**: One of the parameters in your GPT formula is required and hasn't been set.

> **Solution**
>
> [Check which parameters are required](https://autosheet.com/docs/gpt-for-excel/gpt-functions/reference) for the GPT function you are using and adjust the formula as needed.

## Text values limited to 255 characters

`Text values in formulas are limited to 255 characters.`

**Problem**: The text value in your formula is too long and exceeds Excel's 255-character limit.

> **Solution**
>
> Insert the text into another cell and reference it in your formula, for example, `=GPT(A1)`, where `A1` contains the text value.
>
> ![Cell A1 contains a long prompt, and cell B1 contains =GPT(A1)](https://autosheet.com/docs/article-images/help/cell-reference-excel.png)

## Functions are stuck on #BUSY

**Problem**: GPT functions fail to execute and remain in a #BUSY! state, even after reopening your file or restarting Excel.

> **Solutions**
>
> - Open the GPT for Excel – Autosheet sidebar before using any GPT functions:
>
>   - On the [ribbon](https://support.microsoft.com/en-US/Office/foundations-experiences/show-or-hide-the-ribbon-in-office), select **Home > GPT for Excel Word – Autosheet**.
>   - Wait for the sidebar to fully load before entering your first GPT formula.
>
> - Delete the GPT formula and undo the deletion to run the formula again.
>
> - Enter a new GPT formula in a different cell. Subsequent functions typically work correctly.
>
> - Use [bulk tools](https://autosheet.com/docs/gpt-for-excel/bulk-tools) to avoid this issue in the future, if your use case allows it.

## GPT functions prefixed with `_xldudf`

**Problem**: After saving, closing, and reopening an Excel workbook, GPT functions start with `=_xldudf_GPT`.

> **Solutions**
>
> - Open the add-in from the **Add-ins** menu: Select **Home > Add-ins > My Add-ins > GPT for Excel Word – Autosheet**.
> - Check that you are using a [supported version of Excel](https://autosheet.com/docs/gpt-for-excel/faq#which-versions-of-excel-are-compatible-with-this-add-in) and install available Office updates.
> - Test the formula in a new blank workbook before changing the original file. If the issue persists, [contact support](https://support.autosheet.com/hc/en-us/requests/new) with the error and your Excel version. If you suspect a conflict with another add-in, ask your IT administrator or support to help find it.