You can increase the size of Outlook attachments in windows 8.1 by using registry editor with the following steps:
- Click on “Win+R” to open “Run” window.
- Type “regedit” in the field provided on Run window.
- Now click on Yes button to open registry editor.
- After that locate this path HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Preferences
- After that double click on ‘MaximumAttachmentSize’. If it does not exist, then click on Edit button and select new button from the drop down menu to add the DWORD value.
- Click on DWORD value.
- Rename the value as ‘MaximumAttachmentSize’.
- After that, double click on this Value.
- Define attachment size limit in KBs.
- Click on “OK”.
I hope this information will be helpful for you.
NOTE: Be careful while making changes with the Registry Value as any mistake could lead to malfunction of the entire machine.
Thanks & Regards