[TYPO3] Errors with bitsoffice extension

[Sandy Matheson]

Hi,

I have just installed the bitsoffice extensionn to test this with both
xml and sxw files and with both when I browse to upload a file I get
an error to say that the file type is not allowed:

1: Fileextension 'xml' not allowed.
(tt_content:186:tx_bitsoffice_office_file)

1: Fileextension 'sxw' not allowed.
(tt_content:186:tx_bitsoffice_office_file)

Again with both file types when I upload a file manually to fileadmin
and try to browse to find this file it does not appear so I cannot
select it.

As both of these should, I think, work in this extension I am very
puzzled!

Any ideas why this error is happening?

Sandy