Project get stuck (hang) while debugging

[vipinbeni]

when i m going to debug this app then on the below line project got hang for a infinite time please help me .
Source dir =C:\temp\Caches
Target Dir= /Library/Caches
Find device working fine but sync device not working after below line ...
var remoteFolder = Path.Combine(targetDirectory, new FileInfo(file).DirectoryName.Substring(file.IndexOf(root) + root.Length + 1)).Replace(@"", "/");

where i m doing wrong