Backup Timeout error

Hello Everyone!
Windows Server r12 urbackup client 2.2.6 does not do full file backup
urbackup server version 2.2.11

mode: internet

error log:
Starting unscheduled incremental file backup…
Scanning for changed hard links on volume of “c:”…
Indexing of “Program Files” done. 2967 filesystem lookups 0 db lookups and 1 db updates
SimpleSolutionKft: Loading file list…
SimpleSolutionKft: Calculating file tree differences…
SimpleSolutionKft: Indexing file entries from last backup…
SimpleSolutionKft: Calculating tree difference size…
SimpleSolutionKft: Linking unchanged and loading new files…
Waiting for file transfers…
Removing snapshot on “SimpleSolutionKft” for path “Program Files” failed: TIMEOUT
Client SimpleSolutionKft went offline.
Waiting for file hashing and copying threads…
Waiting for metadata download stream to finish
Writing new file list…
All metadata was present
Transferred 36.2023 GB - Average speed: 38.8136 MBit/s
(Before compression: 42.4507 GB ratio: 1.1726)
102.201 GB of files were already present on the server and did not need to be transferred
Time taken for backing up client SimpleSolutionKft: 3h 44s
Backup failed

what’s the problem?

Errors

2018.08.31 05:38
Error getting file metadata. Errorcode: TIMEOUT (2)
Errors

2018.08.31 05:38
Error getting complete file “HlrRqtYQm4HHsBjKwX7r|Program Files/Microsoft SQL Server/MSSQL13.MSSQLSERVER/MSSQL/DATA/corrigan.ldf” from SimpleSolutionKft. Errorcode: TIMEOUT (2)
Errors

2018.08.31 05:38
Client SimpleSolutionKft went offline.
Errors

2018.08.31 05:38
Backup failed