Failing to copy directories recursively

I am trying to migrate my website to bucket using following command
`gsutil rsync -d -R ./www gs://admin.mydomain.com`
but it results following error
```
Building synchronization state...
Caught non-retryable exception while listing file://.\www: [Error 123] The filename, directory name, or volume label syntax is incorrect: u'.\\www\\assets\\icon\\contracts\\?pest-control.svg'
CommandException: Caught non-retryable exception - aborting rsync
```
my actual file path contains no ?, space or anything