Microsoft ended support for Windows XP on [April 8th, 2014](https://www.microsoft.com/en-us/WindowsForBusiness/end-of-xp-support),
an OS initially released in 2001. This means that not even critical security
updates will be released anymore. Without security updates, using a litecoin
wallet on a XP machine is irresponsible at least.
If you are running an older version, shut it down. Wait until it has completely
shut down (which might take a few minutes for older versions), then run the
installer (on Windows) or just copy over `/Applications/Litecoin-Qt` (on Mac)
or `litecoind`/`litecoin-qt` (on Linux).
The first time you run version 0.15.0 or higher, your chainstate database will
be converted to a new format, which will take anywhere from a few minutes to
half an hour, depending on the speed of your machine.
In addition to that, with 0.12.x there have been varied reports of Bitcoin Core
randomly crashing on Windows XP. It is [not clear](https://github.com/bitcoin/bitcoin/issues/7681#issuecomment-217439891)
what the source of these crashes is, but it is likely that upstream
libraries such as Qt are no longer being tested on XP.
The file format of `fee_estimates.dat` changed in version 0.15.0. Hence, a
downgrade from version 0.15 or upgrade to version 0.15 will cause all fee
estimates to be discarded.
We do not have time nor resources to provide support for an OS that is
end-of-life. From 0.13.0 on, Windows XP is no longer supported. Users are
suggested to upgrade to a newer version of Windows, or install an alternative OS
that is supported.
Note that the block database format also changed in version 0.8.0 and there is no
automatic upgrade code from before version 0.8 to version 0.15.0. Upgrading
directly from 0.7.x and earlier without redownloading the blockchain is not supported.
However, as usual, old wallet versions are still supported.
No attempt is made to prevent installing or running the software on Windows XP,
you can still do so at your own risk, but do not expect it to work: do not
report issues about Windows XP to the issue tracker.
Downgrading warning
-------------------
The chainstate database for this release is not compatible with previous
releases, so if you run 0.15 and then decide to switch back to any
older version, you will need to run the old release with the `-reindex-chainstate`
option to rebuild the chainstate data structures in the old format.
If your node has pruning enabled, this will entail re-downloading and
processing the entire blockchain.
Compatibility
==============
Litecoin Core is extensively tested on multiple operating systems using
the Linux kernel, macOS 10.8+, and Windows Vista and later. Windows XP is not supported.
Litecoin Core should also work on most other Unix-like systems but is not
frequently tested on them.
From 0.13.1 onwards OS X 10.7 is no longer supported. 0.13.0 was intended to work on 10.7+,
but severe issues with the libc++ version on 10.7.x keep it from running reliably.
0.13.1 now requires 10.8+, and will communicate that to 10.7 users, rather than crashing unexpectedly.
Notable changes
===============
Network fork safety enhancements
--------------------------------
A number of changes to the way Litecoin Core deals with peer connections and invalid blocks
have been made, as a safety precaution against blockchain forks and misbehaving peers.
- Unrequested blocks with less work than the minimum-chain-work are now no longer processed even
if they have more work than the tip (a potential issue during IBD where the tip may have low-work).
This prevents peers wasting the resources of a node.
- Peers which provide a chain with less work than the minimum-chain-work during IBD will now be disconnected.
- For a given outbound peer, we now check whether their best known block has at least as much work as our tip. If it
doesn't, and if we still haven't heard about a block with sufficient work after a 20 minute timeout, then we send
a single getheaders message, and wait 2 more minutes. If after two minutes their best known block has insufficient
work, we disconnect that peer. We protect 4 of our outbound peers from being disconnected by this logic to prevent
excessive network topology changes as a result of this algorithm, while still ensuring that we have a reasonable
number of nodes not known to be on bogus chains.
- Outbound (non-manual) peers that serve us block headers that are already known to be invalid (other than compact
block announcements, because BIP 152 explicitly permits nodes to relay compact blocks before fully validating them)
will now be disconnected.
- If the chain tip has not been advanced for over 30 minutes, we now assume the tip may be stale and will try to connect
to an additional outbound peer. A periodic check ensures that if this extra peer connection is in use, we will disconnect
the peer that least recently announced a new block.
- The set of all known invalid-themselves blocks (i.e. blocks which we attempted to connect but which were found to be
invalid) are now tracked and used to check if new headers build on an invalid chain. This ensures that everything that
descends from an invalid block is marked as such.
Minimum relay fee lowered
-------------------------
The minimum relay fee `-minrelayfee` has been lowered to 0.01 lites per kB (0.00001 LTC). This is to prepare for dropping the minimum transaction fee to 0.1 lites per kB (0.0001 LTC) in the next release.
Mempool replacement disabled by default
---------------------------------------
Mempool replacement `--mempoolreplacement` has been disabled by default.
Miner block size limiting deprecated
------------------------------------
Though blockmaxweight has been preferred for limiting the size of blocks returned by
getblocktemplate since 0.13.0, blockmaxsize remained as an option for those who wished
to limit their block size directly. Using this option resulted in a few UI issues as
well as non-optimal fee selection and ever-so-slightly worse performance, and has thus
now been deprecated. Further, the blockmaxsize option is now used only to calculate an
implied blockmaxweight, instead of limiting block size directly. Any miners who wish
to limit their blocks by size, instead of by weight, will have to do so manually by
removing transactions from their block template directly.
GUI settings backed up on reset
-------------------------------
The GUI settings will now be written to `guisettings.ini.bak` in the data directory before wiping them when
the `-resetguisettings` argument is used. This can be used to retroactively troubleshoot issues due to the
GUI settings.
Duplicate wallets disallowed
----------------------------
Previously, it was possible to open the same wallet twice by manually copying the wallet file, causing
issues when both were opened simultaneously. It is no longer possible to open copies of the same wallet.
Debug `-minimumchainwork` argument added
----------------------------------------
A hidden debug argument `-minimumchainwork` has been added to allow a custom minimum work value to be used
when validating a chain.
Low-level RPC changes
----------------------
- The "currentblocksize" value in getmininginfo has been removed.
- `dumpwallet` no longer allows overwriting files. This is a security measure
as well as prevents dangerous user mistakes.
- `backupwallet` will now fail when attempting to backup to source file, rather than
destroying the wallet.
- `listsinceblock` will now throw an error if an unknown `blockhash` argument
value is passed, instead of returning a list of all wallet transactions since
the genesis block. The behaviour is unchanged when an empty string is provided.
0.15.1 Change log
=================
### Mining
- #11100`7871a7d` Fix confusing blockmax{size,weight} options, dont default to throwing away money (TheBlueMatt)
### RPC and other APIs
- #10859`2a5d099` gettxout: Slightly improve doc and tests (jtimon)
- #11267`b1a6c94` update cli for estimate\*fee argument rename (laanwj)
- #11483`20cdc2b` Fix importmulti bug when importing an already imported key (pedrobranco)
- #9937`a43be5b` Prevent `dumpwallet` from overwriting files (laanwj)
- #11465`405e069` Update named args documentation for importprivkey (dusty-wil)
Adrian Gallagher
7 years ago