"Error opening block database" after regular startup. Works again once after each fresh install.

[Compunologist]

Happy New Year everybody!

Describe the issue

I have installed Bitcoin Core (64-bit) and changed the data directory to one on my NAS. I ran Bitcoin Core and after 2 days of synchronizing the Bitcoin Core window shows "Up to date". The program exits without any problems.

After each following regular startup however Bitcoin Core (64-bit) reports "Error opening block database. Do your want to rebuild the block database now?" and I have to abort the operation.

When I install Bitcoin Core again and choose to "Run Bitcoin Core (64-bit)" everything works again, including the already synchronized blocks.

Can you reliably reproduce the issue?

If so, please list the steps to reproduce below:

1. Start Bitcoin Core
2. Message: "Error opening block database. Do your want to rebuild the block database now?"

3. Run the Bitcoin Core installer again: "bitcoin-0.13.1-win64-setup.exe"
4. Choose "Run Bitcoin Core (64-bit)", everything works again

What version of bitcoin-core are you using?

Bitcoin Core version v0.13.1 (64-bit)

Machine specs:

• OS: Windows 10 Pro
• CPU: Intel Core i7
• RAM: 8.00 GB
• Disk size: 256GB & 4TB
• Disk Type (HD/SDD): SSD & HD

Any extra information that might be useful in the debugging process.

This is how the debug.log looks like when the error occurs:
Bitcoin debug_not working on regular startup.txt

This is how the debug.log looks like after a reinstall with Bitcoin Core correctly running:
Bitcoin debug_working again after fresh install.txt

[maflcko]

Relevant highlights from debug.log:

2017-01-01 18:33:00 GUI: "registerShutdownBlockReason: Successfully registered: Bitcoin Core didn't yet exit safely..."
[...]
2017-01-01 18:33:01 Opening LevelDB in \\diskstation\incoming\Bitcoin\blocks\index
2017-01-01 18:33:01 IO error: C:\Program Files\Bitcoin\\diskstation\incoming\Bitcoin\blocks\index\LOCK: Could not lock file.

[robmcl4]

I suspect the problem exists in src/leveldb/util/env_win.cc in ModifyPath(), which assumes paths beginning with a backslash are relative paths.

[unsystemizer]

NAS? Has Bitcoin on Windows ever supported SMB? I don't think it did.
Furthermore, #3641 (comment)

[jonasschnelli]

AFAIK LevelDB doesn't support SMB/AFP and other network based file-systems.

[jonasschnelli]

Duplicate of #9157. Closing