Files with long names and some folders exist but are invisible in Windows Explorer

I have created a vault on my SSD. When copying files into it, I noticed in Windows File Explorer that files with long filenames become invisible, where “long” seems to mean longer than 142 characters, without “.extension” and without the path. That is, they are visible for some minutes (say 5), but then they disappear from Explorer. Similarly, if I lock the vault and then unlock, then the files are invisible right away. I have read several posts related to file invisibility, but I have not been able to solve my problem using the proposed solutions.

I notice a potentially related problem regarding folders: after copying into the vault some are invisible (but exist), and if I remove them and copy again from the source into the vault, then the folder remains visible. The latter contrasts with the file problem, because files become invisible again.

I am new to Cryptomator, so perhaps I overlook some relevant setting or so. Of course, I could manually shorten the long filenames, but then I may overlook files in the future. I hope you can resolve my invisibility problem or make sure that Cryptomator issues a warning if files with long filenames are copied into the vault. Thank you.

Further details:

  • I use Cryptomator 1.6.0 on Windows 10 Education, Version 21H1, OS build 19043.1288.
  • A simple example to facilitate replication: add a new vault on C:\Users<MyName>, password aaaaaaaa, unlock the vault. Now copy two empty text files into the vault, one with filename b…b142.txt and the other with filename b…bb143.txt, where “b…b” is a string of 139 times “b”, so that the total filenames contain 142 and 143 characters, respectively. Lock and unlock the vault. The …142.txt is still visible, but …143.txt is not.
  • Unsuccessful trials: writing something in the file so that it is no longer empty; using another extension than txt; changing from WinDav to Dokany or FUSE; opening file explorers of other programs such as Notepad and Word; creating the vault in OneDrive instead of my own SSD.
  • Methods for learning that the files exist: 1) If I try to copy another file with the same name to the vault, Explorer asks me whether I want to overwrite the (invisible) file. 2) In the encrypted “d” folder I notice that each invisible file leads to a folder with two files (name.c9s and contents.c9r). 3) Health Check gives an error for “Shortened Names Check”. After clicking “Fix” and running the Health Check again, the error is gone, but the file is still invisible.

Same here, exactly same issue.
Windows 10 Pro N, 21H1, build 19043.1348
Cryptomator 1.6.1 (msi-3338), portable

When Health Check, it displays the following:

STATUS: SUCCESS
RESULTS:
    WARN - Name of D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\1Rk--QS2b2Z2MYsuRV5WeCD7u38=.c9s is not a base64url encoded SHA1 hash of String inside name.c9s.
    WARN - Name of D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\M38x43T76hxMZPkaCXlxRh-dm_w=.c9s is not a base64url encoded SHA1 hash of String inside name.c9s.
    WARN - Name of D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\VZGmTlbR9wZ7FylAOuwPFwCFZ00=.c9s is not a base64url encoded SHA1 hash of String inside name.c9s.
    WARN - Name of D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\xxLN4ZV8rEhlcS7hC_1UqpXNDlg=.c9s is not a base64url encoded SHA1 hash of String inside name.c9s.

Log file displays a lot of lines like this:

03:01:55.547 [JavaFX Application Thread] INFO  o.cryptomator.ui.common.VaultService - Revealed Test
03:01:59.163 [dokanMount-1-callback-0] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\DIkruKWmbem36pXRgWHaBJtqae4=.c9s's inflated filename could not be decrypted.
03:01:59.172 [dokanMount-1-callback-0] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\NKDnBWL0R34fck1n7gQN8qI2uMo=.c9s's inflated filename could not be decrypted.
03:01:59.185 [dokanMount-1-callback-0] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\XG65lM-um93uoGivm1K3L0hJwtw=.c9s's inflated filename could not be decrypted.
03:01:59.187 [dokanMount-1-callback-0] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\Z4gzR2Q9RATlvddbMQImjtt-EEw=.c9s's inflated filename could not be decrypted.
03:02:00.680 [dokanMount-1-callback-1] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\DIkruKWmbem36pXRgWHaBJtqae4=.c9s's inflated filename could not be decrypted.
03:02:00.684 [dokanMount-1-callback-1] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\NKDnBWL0R34fck1n7gQN8qI2uMo=.c9s's inflated filename could not be decrypted.
03:02:00.698 [dokanMount-1-callback-1] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\XG65lM-um93uoGivm1K3L0hJwtw=.c9s's inflated filename could not be decrypted.
03:02:00.700 [dokanMount-1-callback-1] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\Z4gzR2Q9RATlvddbMQImjtt-EEw=.c9s's inflated filename could not be decrypted.
03:02:00.815 [dokanMount-1-callback-2] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\DIkruKWmbem36pXRgWHaBJtqae4=.c9s's inflated filename could not be decrypted.
03:02:00.821 [dokanMount-1-callback-2] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\NKDnBWL0R34fck1n7gQN8qI2uMo=.c9s's inflated filename could not be decrypted.
03:02:00.839 [dokanMount-1-callback-2] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\XG65lM-um93uoGivm1K3L0hJwtw=.c9s's inflated filename could not be decrypted.
03:02:00.840 [dokanMount-1-callback-2] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\Z4gzR2Q9RATlvddbMQImjtt-EEw=.c9s's inflated filename could not be decrypted.
03:02:00.968 [dokanMount-1-callback-3] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\DIkruKWmbem36pXRgWHaBJtqae4=.c9s's inflated filename could not be decrypted.
03:02:00.972 [dokanMount-1-callback-3] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\NKDnBWL0R34fck1n7gQN8qI2uMo=.c9s's inflated filename could not be decrypted.
03:02:00.980 [dokanMount-1-callback-3] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\XG65lM-um93uoGivm1K3L0hJwtw=.c9s's inflated filename could not be decrypted.
03:02:00.981 [dokanMount-1-callback-3] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\Z4gzR2Q9RATlvddbMQImjtt-EEw=.c9s's inflated filename could not be decrypted.
03:02:01.039 [dokanMount-1-callback-4] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\DIkruKWmbem36pXRgWHaBJtqae4=.c9s's inflated filename could not be decrypted.
03:02:01.042 [dokanMount-1-callback-4] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\NKDnBWL0R34fck1n7gQN8qI2uMo=.c9s's inflated filename could not be decrypted.
03:02:01.050 [dokanMount-1-callback-4] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\XG65lM-um93uoGivm1K3L0hJwtw=.c9s's inflated filename could not be decrypted.
03:02:01.051 [dokanMount-1-callback-4] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\Z4gzR2Q9RATlvddbMQImjtt-EEw=.c9s's inflated filename could not be decrypted.
03:02:01.247 [dokanMount-1-callback-1] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\DIkruKWmbem36pXRgWHaBJtqae4=.c9s's inflated filename could not be decrypted.
03:02:01.252 [dokanMount-1-callback-1] WARN  o.c.cryptofs.dir.C9sInflator - D:\OneDrive\Test_Cryptomator\Test\d\N2\VQY6BC6OIYNMLC6XIVJ6ODXCYAEE2S\NKDnBWL0R34fck1n7gQN8qI2uMo=.c9s's inflated filename could not be decrypted.