How to block some files in Sharepoint 2010.
1. Goto Central Administration and click Security.
2. On the Security page, in the General Security section, click Define blocked file types.
3. On the Blocked File Types page, Select the desired Web Application.
4. To block a file type, scroll to the bottom of the Type each file extension on a separate line text box and type the file extension you want to block and then click OK.
To Unblock :
just Select the File type and Delete it.
1. Goto Central Administration and click Security.
2. On the Security page, in the General Security section, click Define blocked file types.
3. On the Blocked File Types page, Select the desired Web Application.
4. To block a file type, scroll to the bottom of the Type each file extension on a separate line text box and type the file extension you want to block and then click OK.
To Unblock :
just Select the File type and Delete it.
