No Stylesheet and Template on Upload

For some reason, the last two times I have tried uploading a wordpress theme with an FTP client, the stylesheet and template have not uploaded. I’m not sure what I am doing wrong. It has been a while since I have uploaded wordpress themes, but have done it successfully in the past. For one of the themes, I manually uploaded the .css stylesheet and it appeared to work but when I looked at the page after activating the theme the header was missing. Any ideas on what I’m doing wrong? Yes, I am uploading to the write place — wp-content, then the themes folder.

[No bumping – especially within 1 hour of first posting. If it’s that urgent, consider hiring someone.]