I imported the PrivBase58 into Electrum wallet and I can see my balance, but it is a watching-only-wallet.
How can I change that so I can send them?
It seems something went wrong with the import into Electrum. If it is "watching-only", then you have not imported the
private key, you have imported the
public key. So, make sure you are copy/pasting the correct field from the Armory export.
These are my recommended settings when exporting from Armory to import the keys into Electrum:
Note that the "PrivBase58" will most likely start with a "5", it should have no spaces (use the "omit spaces" option as shown) and it should be 51 characters long.
You should be able to import this into Electrum using the "Import Bitcoin Address or private keys" option when creating a wallet:
And simply paste in the
private key(s) that match the address(es) that you sent coins to:
This will create an "imported" wallet with the address(es) and you should be able to send: