Our users store the email attachments in FB03 using Store Business Document option. The attachments gets saved correctly, and when we try to display a excel file we gets the dialog box to open or save the file and the file opens correctly. If it is a .msg file, then the dialog box appears but there is no extension for the file name in dialog box.
Our users were able to open .msg files also without any issues till few weeks back and the issue started to occur suddenly. We have configured everything as mentioned in SAP KBA 1840170 and made some changes as specified in SCN discussion https://archive.sap.com/discussions/thread/1770876. We even tried the registry editing option, but doesn't work. Please share your inputs