Can't upload xlsx files because of a warning

Hi,

I get the following warning:
Warning: file_get_contents() [function.file-get-contents]: Filename cannot be empty in /home/xxx/domains/xxx.com/public_html/xxx/wp-content/plugins/wp-excel-cms/admin/wp-excel-cms-admin.php on line 242

Line 242 =
$file_data[$i] = (array) json_decode(file_get_contents($files[$i]));

I think that because of the warning I can’t see the upload screen. Every time I try to upload a file in the ‘already uploaded’ section it tells me: Upload failed! Please give it a Name and Select a File.

The created upload folder has all the right permissions to upload files.

Hope you have some time to take a look at this.

M.

https://wordpress.org/plugins/wp-excel-cms/