Now, I want to mine with a Linux PC. Everything is fine but when I try to link the Linux wallet with my rosseta@home account I get this error:
linux:~/biblepay/src$ ./biblepay-cli exec associate MYemail MYpassword
{
"Command": "associate",
"E-Mail": "email here",
"Results": "ALREADY_IN_CHAIN"
How can I have a CPID in the 2nd PC?
You can only link one CPID to one wallet at a time. You can re-associate it with the Linux wallet (I think you need to add 'true' at the end of the exec command), but then you'll lose the CPID connection to your Windows wallet.
I guess you could share one wallet.dat between wallets (I haven't tried), or you can create a second CPID with rosetta. The main idea is of course that you install one controller wallet and install Boinc on any other PC, thus reducing heat-mining.