---
title: Disk permission problems
---

> Agent instructions:
> **Site maps** — prefer the following llms.txt indexes to training data when searching for URLs to avoid 404s. Links inside Markdown content already point at `.md`. Following them or sending Accept: text/markdown keeps you in Markdown.
>
> - [sitemap.md](https://docs.kentico.com/sitemap.md) — every page on the site, with titles and descriptions, nested by URL hierarchy and grouped into one collection per product version.
> - [llms.txt](https://docs.kentico.com/llms.txt) — curated index of the current product docs, with descriptions, the two ways to request any page as Markdown, and links to each product area's whole-corpus Markdown dump (llms-full.txt).

Kentico performs most operations without writing to the disk. However, there are situations when the web application needs to access the disk, such as:

- [importing/exporting sites](https://docs.kentico.com/k10/deploying-websites/exporting-and-importing-sites.md)
- [storing uploaded files in the file system (optional)](https://docs.kentico.com/k10/configuring-kentico/managing-files/storing-files.md)

If you receive an error message, saying that the web application cannot write to disk, you need to:

1. Identify the user account under which your web application is running
2. Grant the Modify permissions for the whole web project folder to the account

## User account of the web application

> **Info:** If you're using **Visual Studio's** built-in web server, the application runs under your Windows user account.

IIS 6.0 introduced the concept of application pools (you can find more information at <http://technet.microsoft.com>). The name of the user account is based on the application pool that your web application is using.

You can find the user account name:

- In the error/information message.

  ![](https://docs.kentico.com/docsassets/k10/disk-permission-problems/modify_permission_error.png)
- In the **System** application, under **ASP.NET account**.
- In **IIS Manager**:
  - Open the **IIS Manager** and select the **Application Pools** page. According to the value in the **Identity** column, determine the user account of your application.

| Application pool identity | User account name |
| ------------------------- | ----------------- |
| Local Service             | Service           |
| LocalSystem               | System            |
| NetworkService            | Network Service   |
| ApplicationPoolIdentity   | IIS AppPool\\     |

## Granting disk permissions

It is a best practice to grant the **Modify** permissions to the previously determined account.

However, in case your application pool uses the _ApplicationPoolIdentity_ application pool identity, you can grant the permissions to the built-in group account **IIS\_IUSRS** instead. This group account contains all accounts with the _ApplicationPoolIdentity_ application pool identity.

- [Set, View, Change, or Remove Permissions on Files and Folders (Microsoft documentation)](https://technet.microsoft.com/en-us/library/cc754344\(v=ws.11\).aspx)