please help!

[frank lin]

gnus you are so great , like emacs the more i use , the more i love ,
but now i come to some problem...

i  am usinig  osx lion 10.73 , emacs24.0.94.1  ,  gnus v 5.13
i use nnimap  and nnrss as my agents , the last time i gnus-agent-
fetch-group , it download all the nnrss, but at last when it came to
nnimp, it seems my mails is too much , there is no message in the
minor buffer , so i press C-g to cancel, after that , i can't get into
the summary mode of nnimap' group , and now when i restart gnus , it
comes out the below messages:
Reading /Users/art/.newsrc.eld...
gnus-read-newsrc-el-file: Wrong type argument: stringp, nil

please help me , and forgive my poor english