Error: "Exception during sync of package json cache" - anyone know what this means?

[Syrinxo]

As stated, I'm getting this error. Have had it for a while and it didn't seem to be affecting anything, so I ignored it, but now I'm trying to solve an asset/VAR problem (assets are loading in for other people at wrong scale/rotation) and figured I'd follow this lead, in case it's relevant.

Thanks in advance to anyone who can figure this out!

Full error:

!> Exception during sync of package json cache: ICSharpCode.SharpZipLib.Zip.ZipException: Size mismatch between central header(233) and local header(0)
  at ICSharpCode.SharpZipLib.Zip.ZipFile.TestLocalHeader (ICSharpCode.SharpZipLib.Zip.ZipEntry entry, HeaderTest tests) [0x00000] in <filename unknown>:0
  at ICSharpCode.SharpZipLib.Zip.ZipFile.LocateEntry (ICSharpCode.SharpZipLib.Zip.ZipEntry entry) [0x00000] in <filename unknown>:0
  at ICSharpCode.SharpZipLib.Zip.ZipFile.GetInputStream (Int64 entryIndex) [0x00000] in <filename unknown>:0
  at ICSharpCode.SharpZipLib.Zip.ZipFile.GetInputStream (ICSharpCode.SharpZipLib.Zip.ZipEntry entry) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarFileEntryStream..ctor (MVR.FileManagement.VarFileEntry entry) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarFileEntryStreamReader..ctor (MVR.FileManagement.VarFileEntry entry) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.FileManager.OpenStreamReader (MVR.FileManagement.FileEntry fe) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.FileManager.ReadAllText (MVR.FileManagement.FileEntry fe) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
  at MVR.FileManagement.VarPackage.SyncJSONCache () [0x00000] in <filename unknown>:0

 

[Case]

I get the same (size mismatch) errormsg, sometimes also the one below (wrong header signature). Also no clue what either of them mean, or how to fix, since "<filename unknown>" ...

!> Exception during sync of package json cache: ICSharpCode.SharpZipLib.Zip.ZipException: Wrong local header signature @B43935
at ICSharpCode.SharpZipLib.Zip.ZipFile.TestLocalHeader (ICSharpCode.SharpZipLib.Zip.ZipEntry entry, HeaderTest tests) [0x00000] in <filename unknown>:0
at ICSharpCode.SharpZipLib.Zip.ZipFile.LocateEntry (ICSharpCode.SharpZipLib.Zip.ZipEntry entry) [0x00000] in <filename unknown>:0
at ICSharpCode.SharpZipLib.Zip.ZipFile.GetInputStream (Int64 entryIndex) [0x00000] in <filename unknown>:0
at ICSharpCode.SharpZipLib.Zip.ZipFile.GetInputStream (ICSharpCode.SharpZipLib.Zip.ZipEntry entry) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarFileEntryStream..ctor (MVR.FileManagement.VarFileEntry entry) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarFileEntryStreamReader..ctor (MVR.FileManagement.VarFileEntry entry) [0x00000] in <filename unknown>:0
at MVR.FileManagement.FileManager.OpenStreamReader (MVR.FileManagement.FileEntry fe) [0x00000] in <filename unknown>:0
at MVR.FileManagement.FileManager.ReadAllText (MVR.FileManagement.FileEntry fe) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.AddDirToCache (MVR.FileManagement.VarDirectoryEntry de, System.String pattern, SimpleJSON.JSONClass cache) [0x00000] in <filename unknown>:0
at MVR.FileManagement.VarPackage.SyncJSONCache () [0x00000] in <filename unknown>:0