namecoin-qt not synchronizing blockchain: "WARNING: Displayed transactions ...

[curiosity81]

... may not be correct! You may need to upgrade, or other nodes may need to upgrade."

I used the Debian namecoin-qt binary from http://namecoin.info/ and it worked fine except that sometimes the blockchain is messed up.

This morning I got the message from above so I downloaded the current source from https://github.com/namecoin-qt/namecoin-qt and built it as described in http://dot-bit.org/BuildNamecoinQTFromSource.

However, the message stays the same and the blockchain is not updated.

What is wrong?

[curiosity81]

... may not be correct! You may need to upgrade, or other nodes may need to upgrade."

I used the Debian namecoin-qt binary from http://namecoin.info/ and it worked fine except that sometimes the blockchain is messed up.

This morning I got the message from above so I downloaded the current source from https://github.com/namecoin-qt/namecoin-qt and built it as described in http://dot-bit.org/BuildNamecoinQTFromSource.

However, the message stays the same and the blockchain is not updated.

What is wrong?

I found this: http://forum.namecoin.info/viewtopic.php?f=7&t=1484

If this works (haven't tested it yet), then it is strange that namecoin-qt always messes up the blockchain.

[Sharrow]

I spent ages yesterday on this for issue for another altcoin and haven't found the cause yet. Removing all the blockchain files doesn't seem to make any difference and it always gets stuck at a specific block, yet the Windows builds work fine?!

[curiosity81]

So what always seems to work is to use a "new" blockchain. On a second computer I always have a partly downloaded blockchain. If the current blockchain is messed up, I synchronize this blockchain using namecoind. If I copy this blockchain and use it instead of the old for namecoin-qt, it works again.

So there are several strange things happening:
  (i) namecoin-qt messes up blockchain, namecoind doesn't;
  (ii) namecoind is much faster than namecoin-qt during synchronizing;
  (iii) actually I always make a backup of a working blockchain using rsync, however, this copy is not accepted by namecoin-qt,
      the program wants to download the whole chain again.

In this "framework" namecoind is executed on a faster computer, but the network connection is the same. The blockchain and the backup is on located on an encrypted usb stick.

Anyone an idea where this problems are coming from?