Hi,

After more testing, I can rule out the disk space problem because I have 1TB free space. I can also rule out the permission problem because this happens during fresh runs.

I discovered the problem I had was due to the use of the Universal Naming Convention (UNC) Path, "\\xx-x411\clamav". Even on the same server where "\\xx-x411\clamav" and "D:\clamav" are the same, the behaviors are different as shown below.

With the "D:\clamav" path, it found that the database is not up to date, then it gets the cld file, and no issues. WIth the UNC path, it downloads the same cvd file and complains that the file exists. I wanted to use the UNC path because I want to share the database across the servers.

Here is the log to show the problem:

PS D:\ClamAV\clamav-0.103.3-win-x64-portable\database> rm -recurse *

PS D:\ClamAV\clamav-0.103.3-win-x64-portable\database> \\xx-x411\clamav\clamav-0.103.3-win-x64-portable\freshclam.exe --datadir=d:\clamav\clamav-0.103.3-win-x64-portable\database
ClamAV update process started at Fri Jul  9 15:48:10 2021
daily database available for download (remote version: 26226)
Time:    3.6s, ETA:    0.0s [========================>]  102.43MiB/102.43MiB
Testing database: 'd:\clamav\clamav-0.103.3-win-x64-portable\database\tmp.1276ba4a31\clamav-7f99d642a7a4902e4a2f435c323e2552.tmp-daily.cvd' ...
Database test passed.
daily.cvd updated (version: 26225, sigs: 3994327, f-level: 63, builder: raynman)
Received an older daily CVD than was advertised. We'll retry so the incremental update will ensure we're up-to-date.
daily database available for update (local version: 26225, remote version: 26226)
Current database is 1 version behind.
Downloading database patch # 26226...
Time:    0.0s, ETA:    0.0s [========================>]   19.36KiB/19.36KiB
Testing database: 'd:\clamav\clamav-0.103.3-win-x64-portable\database\tmp.1276ba4a31\clamav-baae84e4ef91bcdfa772d7d82c8af6f8.tmp-daily.cld' ...
Database test passed.
daily.cld updated (version: 26226, sigs: 3994579, f-level: 63, builder: raynman)
main database available for download (remote version: 59)
Time:    4.0s, ETA:    0.0s [========================>]  112.40MiB/112.40MiB
Testing database: 'd:\clamav\clamav-0.103.3-win-x64-portable\database\tmp.1276ba4a31\clamav-046d7008715c9c8fba4d462be7120643.tmp-main.cvd' ...
Database test passed.
main.cvd updated (version: 59, sigs: 4564902, f-level: 60, builder: sigmgr)
bytecode database available for download (remote version: 333)
Time:    0.1s, ETA:    0.0s [========================>]  286.79KiB/286.79KiB
Testing database: 'd:\clamav\clamav-0.103.3-win-x64-portable\database\tmp.1276ba4a31\clamav-f4500f3362769ec4bcbdfcaa854f
cfb8.tmp-bytecode.cvd' ...
Database test passed.
bytecode.cvd updated (version: 333, sigs: 92, f-level: 63, builder: awillia2)

PS D:\ClamAV\clamav-0.103.3-win-x64-portable\database> rm -recurse *

PS D:\ClamAV\clamav-0.103.3-win-x64-portable\database> \\xx-x411\clamav\clamav-0.103.3-win-x64-portable\freshclam.exe --datadir=\\xx-x411\clamav\clamav-0.103.3-win-x64-portable\database
ClamAV update process started at Fri Jul  9 15:51:05 2021
daily database available for download (remote version: 26226)
Time:    4.1s, ETA:    0.0s [========================>]  102.43MiB/102.43MiB
Testing database: '\\xx-x411\clamav\clamav-0.103.3-win-x64-portable\database\tmp.dcd8c0cb40\clamav-a9ada8b934fb64989e60cabb093b72ec.tmp-daily.cvd' ...
Database test passed.
daily.cvd updated (version: 26225, sigs: 3994327, f-level: 63, builder: raynman)
Received an older daily CVD than was advertised. We'll retry so the incremental update will ensure we're up-to-date.
daily database available for download (remote version: 26226)
Time:    3.8s, ETA:    0.0s [========================>]  102.43MiB/102.43MiB
Testing database: '\\xx-x411\clamav\clamav-0.103.3-win-x64-portable\database\tmp.dcd8c0cb40\clamav-907671efc5b51d897ec211313228eb86.tmp-daily.cvd' ...
Database test passed.
ERROR: updatedb: Can't rename \\xx-x411\clamav\clamav-0.103.3-win-x64-portable\database\tmp.dcd8c0cb40\clamav-907671efc5b51d897ec211313228eb86.tmp-daily.cvd to daily.cvd: File exists
ERROR: Unexpected error when attempting to update daily: Failed to read/write file to database directory
ERROR: Database update process failed: Failed to read/write file to database directory
ERROR: Update failed.