Upload of self-created PP presentations in Gmail stuck in Firefox

[Simplici7y]

Every time I try to upload a self-created (or modified) PP presentation in Gmail, it uploads to a certain point (about 2/3) and then stops. Tried it multiple times, tried completely deleting Firefox (along with personal data+extensions), still doesn't work. Uploading, however, does work in HTML mode and in IE.

The problem started happening after installation of Kaspersky Internet Security (with legal license). Any ideas as to how to fix this?

 

[Phillip Corcoran]

Uninstall KIS, use an alternative.

 

[Tradesman1]

What size is the attachment, GMail has a size limit on attachments