[Home](./index.md) > [bitburner](./bitburner.md) > [NS](./bitburner.ns.md) > [fileExists](./bitburner.ns.fileexists.md)
## NS.fileExists() method
Returns a boolean indicating whether the specified file exists on the target server. The filename for scripts is case-sensitive, but for other types of files it is not. For example, fileExists(“brutessh.exe”) will work fine, even though the actual program is named 'BruteSSH.exe'.
If the hostname/ip argument is omitted, then the function will search through the current server (the server running the script that calls this function) for the file.
Signature:
```typescript
fileExists(filename: string, host?: string): boolean;
```
## Parameters
| Parameter | Type | Description |
| --- | --- | --- |
| filename | string | Filename of file to check. |
| host | string | Host or IP of target server. This is optional. If it is not specified then the function will use the current server as the target server. |
Returns:
boolean
True if specified file exists, and false otherwise.
## Remarks
RAM cost: 0.1 GB
## Example 1
```ts
//The function call will return true if the script named foo.script exists on the foodnstuff server, and false otherwise.
fileExists("foo.script", "foodnstuff");
```
## Example 2
```ts
//The function call will return true if the current server contains the FTPCrack.exe program, and false otherwise.
fileExists("ftpcrack.exe");
```