I am getting error message SO322: Document of this type is not allowed in your system, while trying to attach any document file (pdf,doc,jpg etc.) in tcode sbwp.
This error is appearing in QA server only. In Dev & Production system I am able to attach document in sbwp without any error.error-in-sbwp-while-attach-document.jpg
SAP Note 2184005 - Error message: Documents of this type are not allowed in your system (SO322) for attachmen... has got a solution for you.
Please compare those settings of QA with Dev/Prod. If that looks same then as mentioned in the Note, it could be on the content server side.
Let me know how you get on.