failed transfers

In a failed transfer (upload)...
In the remote folder there are files called:

.pureftpd-upload.4317887e.15.7ffa.66b9ce72
.pureftpd-upload.43178978.15.631.cef2b741
.pureftpd-upload.43178aac.15.d60.4dd2b683

The server won't let me delete these files,
won't let me rename the files
won't let me change permissions on these files
they don't resume, they start new ones

How do I get rid of them?
Can they be resumed where they left off?

TIA

Sorry...forgot to tell you what I am using...

SmartFTP version 1.5 version 1.5.990.4