they start with U2Fs have some funds in there from way back not a lot but a few bits when I try to sweep them would not allow me to do so as the button is grayed out i have the key file as I have extracted it
Those are encrypted.
Do you still have access to your Multibit wallet?
If you do, make a new unencrypted private key export file by
not ticking "
password protect export file" when exporting the keys.
If you do not have access to the wallet, you have to use other tools to decrypt it.
Example: BTCRecover has an export-script that accepts MultiBit's private key export file, but I haven't tested it.
Link:
extract-multibit-privkey.py - from:
github.com/3rdIteration/btcrecover/tree/master/extract-scriptsHCP also has a post with steps to decrypt encrypted PrvKeys export file:
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