# Thread 'main' panicked at 'reader failed: **URL:** \ **Category:** Support and Troubleshooting\ **Created:** [November 19, 2021, 1:42pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763 "2021-11-19T13:42:36Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![juhurus](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.umbrel.com/juhurus/32/134_2.png) [@juhurus](https://community.umbrel.com/u/juhurus)\ **Post date:** [November 19, 2021, 1:42pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763/1 "2021-11-19T13:42:36Z")
Still having issues to update to any version higher than 0.4.3-build-1c80170. As a part me learning and investigating the issue I ran the command to reindex (sudo systemctl stop umbrel-startup && sudo rm -rf ~/umbrel/electrs/!(electrs.toml) && sudo systemctl start umbrel-startup) which gives me the following error below. Does that perhaps mean that the file blk00540.dat is corrupt? Shouldn’t the reindexing fix such error? How can that get fixed? Any help would be much appreciated. BTW: Reindexing always stops at the same file(blk00540.dat) and starts over and over again from the beginning. electrs | TRACE - indexed “/data/.bitcoin/blocks/blk00538.dat”: 0 rows electrs | DEBUG - no more blocks to index electrs | DEBUG - no more blocks to index electrs | TRACE - indexed “/data/.bitcoin/blocks/blk00539.dat”: 0 rows electrs | DEBUG - no more blocks to index electrs | DEBUG - no more blocks to index electrs | TRACE - indexed “/data/.bitcoin/blocks/blk00540.dat”: 0 rows electrs | thread ‘main’ panicked at ‘reader failed: Error(Msg(“failed to read “/data/.bitcoin/blocks/blk00541.dat””), State { next\_error: Some(Os { code: 5, kind: Other, message: “Input/output error” }), backtrace: InternalBacktrace { backtrace: None } })’, src/libcore/result.rs:1188:5 electrs | note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace. electrs | TRACE - closing DB at “/data/db/mainnet” electrs | Config { log: StdErrLog { verbosity: Trace, quiet: false, show\_level: true, timestamp: Off, modules: [], writer: “stderr”, color\_choice: Never }, network\_type: Bitcoin, db\_path: “/data/db/mainnet”, daemon\_dir: “/data/.bitcoin”, blocks\_dir: “/data/.bitcoin/blocks”, daemon\_rpc\_addr: V4(10.21.21.8:8332), electrum\_rpc\_addr: V4(0.0.0.0:50001), monitoring\_addr: V4(127.0.0.1:4224), jsonrpc\_import: false, index\_batch\_size: 10, bulk\_index\_threads: 4, tx\_cache\_size: 10485760, txid\_limit: 100, server\_banner: “Umbrel v0.4.3”, blocktxids\_cache\_size: 10485760 } electrs | DEBUG - Server listening on 127.0.0.1:4224 electrs | DEBUG - Running accept thread electrs | INFO - NetworkInfo { version: 210100, subversion: “/Satoshi:0.21.1/”, relayfee: 0.00001 } electrs | INFO - BlockchainInfo { chain: “main”, blocks: 710426, headers: 710426, verificationprogress: 0.9999989087659374, bestblockhash: “000000000000000000017019b6a0878917a9738f09c261fd97915b48ad785a8c”, pruned: false, initialblockdownload: false } electrs | DEBUG - opening DB at “/data/db/mainnet” electrs | TRACE - latest indexed blockhash: 0000000000000000000000000000000000000000000000000000000000000000 electrs | INFO - listing block files at “/data/.bitcoin/blocks/blk\*.dat” electrs | INFO - indexing 2812 blk\*.dat files electrs | DEBUG - found 415727 indexed blocks electrs | TRACE - downloading 100000 block headers ---
**Author:** ![DarthCoin](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.umbrel.com/darthcoin/32/1628_2.png) [@DarthCoin](https://community.umbrel.com/u/DarthCoin)\ **Post date:** [November 19, 2021, 1:47pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763/2 "2021-11-19T13:47:08Z")
yes, is corrupted. if you could obtain it from another synced node and replace that file manually, it could work. Electrs will create a new index but should start again. Worth trying. Other option is to wipe block data folder (not all node) and let the node to sync again. Is clean and better. But if your drive had some hardware issues, maybe you will end again in this situation. So a format and start over is more indicated. Anyway, try first copying that only file. Of course with node shut down. Just take the drive to anotehr PC and copy the file and put it back ---
**Author:** ![juhurus](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.umbrel.com/juhurus/32/134_2.png) [@juhurus](https://community.umbrel.com/u/juhurus)\ **Post date:** [November 19, 2021, 1:53pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763/3 "2021-11-19T13:53:13Z")
Unfortunately I don’t have access to copy of that file(blk00540.dat). Can this be downloaded somewhere? Would you or someone else be able to attach a copy for me? ---
**Author:** ![DarthCoin](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.umbrel.com/darthcoin/32/1628_2.png) [@DarthCoin](https://community.umbrel.com/u/DarthCoin)\ **Post date:** [November 19, 2021, 1:57pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763/4 "2021-11-19T13:57:28Z")
You could download the blockchain torrent See the instruction I put in the troubleshooting manual about copying the blockchain data > [@Umbrel Troubleshooting Guide](http://community.umbrel.com/t/umbrel-troubleshooting-guide/3632): > > Edit by moderators The new, official troubleshooting guide can be found here: Huge thanks to DarthCoin for writing and maintaining the previous community version of the guide. ---
**Author:** ![juhurus](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.umbrel.com/juhurus/32/134_2.png) [@juhurus](https://community.umbrel.com/u/juhurus)\ **Post date:** [November 19, 2021, 2:02pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763/5 "2021-11-19T14:02:29Z")
great, thanks a lot, downloading now ---
**Author:** ![juhurus](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.umbrel.com/juhurus/32/134_2.png) [@juhurus](https://community.umbrel.com/u/juhurus)\ **Post date:** [November 20, 2021, 1:35pm UTC](https://community.umbrel.com/t/thread-main-panicked-at-reader-failed/4763/6 "2021-11-20T13:35:43Z")
Hmm, apparently the blockchain cannot be downloaded from any of the links in the troubleshooting guide. The readme here [https://bitcoincore.org/bin/block-chain/README.txt](https://bitcoincore.org/bin/block-chain/README.txt) says: “This directory used to contain a torrent of the bitcoin block chain. It had not been updated since 2017 so was effectively useless, so has been removed. The best way to download the block chain is to run the client, which downloads it through bitcoin’s own P2P network.” Will try option 2 now and re-download the whole blockchain.