Hi , I have a quick question here .
How to upgrade from a version to another new version (of Electrum) ? I simply install the other or I should unistall the old one , also does the seed works on different wallets , I mean a seed of 2.3 version should work fine on the 2.4 version ?
Yes, it works! Backup your Electrum wallet file(s) and install latest version.
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Should I uninstall the old wallet before installing a new version?
It's not necessary, but it doesn't hurt either.
(I will do multiple local and remote backups of my wallet before doing any installs or upgrades.)
That's always a good idea, but it also shouldn't be necessary. The only thing to be aware of is that Electrum 2.x will upgrade your wallet format. In order to downgrade to a 1.x version (not that you ever should need to), you'll either need to restore your wallet from it's seed or use a backup from before you upgrade.
Side note: if you do remote backups, be sure you've got a strong password on the wallet, or use a zero-knowledge backup provider such as SpiderOak (and a strong password with them).
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Finally, once the installation on the 10.9.5 system is completed and confirmed, is there any point of keeping the 1.9.8 wallet?
nerioseole alluded to one above—Electrum 2.x uses a different wallet format. If you give it a 1.9.8 wallet file, it will upgrade it to the new format behind the scenes (the seed remains the same). If you ever want to copy this 2.x wallet file to a machine that has Electrum 1.x on it, you'll need to instead either:
- Use a backup from Electrum 1.x, or
- simply restore from the seed.