The maximum file size (per file upload) is set on the Uploading screen. You can allow upload of files sized up to 100 MB. The Uploading option also gives you control over the types of files that users are allowed to upload. You can add a new extension for file types that are not already allowed (such as the Office 2007 file types: docx, pptx, and xlsx).
Enabling file type uploads - Choose 'Uploading' from the Admin drop-down menu. Click the ‘Add New Upload Extension’ link. Enter the extension and a brief description. In the ‘Filename for Icon’ drop down menu, choose the type of file that the extension refers to. For example, in Figure 1 the extension that we are adding (i.e., docx) refers to a Word document.
Setting the image icon for the file type -
Troubleshooting file uploads - If you have added an extension and you still cannot upload the file of that type, check to be sure that you have not included a period in front of the extension name. The extension should be entered as ‘docx’, ‘pptx’, not ‘.docx’ or ‘.pptx’.