You've to either double "\" or prefix a string with "@" to turn off escape characters recognition.

string ConnectionString = "Provider=vfpoledb.1;Data Source=c:\\datadotnet\\vfp\bin\debug\\samples.dbc";
string ConnectionString = @"Provider=vfpoledb.1;Data Source=c:\datadotnet\vfp\bin\debug\samples.dbc";

>string ConnectionString = "Provider=vfpoledb.1;Data Source=c:\datadotnet\vfp\bin\debug\samples.dbc";
>
>This is ONE line in the program.
>
>I get unrecognized escape sequence
>
>I have renamed the old vfpoledb to vfpoledb7 and I did register the vfpoledb from vfp8
>
>
>Leo