Serial connection issue on windows

Hello everyone
I use octoprint for about a year, installed on a PC with windows 8.1 and never had problems of disconnection.
The printer (an I3 prusa) is connected via a USB cable, and the other USB devices are a webcam, keyboard and mouse.
Lately I have several problems of disconnection two out of three prints do not end.
I read in the forums, but almost everyone has a raspberry and no windows, can anyone help me? I attach my log that I can not interpret
thank you

2018-05-16 13:45:26,921 - octoprint.server - INFO - ------------------------------------------------------------------------------
2018-05-16 13:45:26,869 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 14:00:26,927 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 14:15:26,934 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 14:30:26,946 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 14:45:26,950 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 15:00:26,961 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 15:15:26,963 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 15:30:26,966 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 15:45:26,973 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 16:00:26,980 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 16:15:26,990 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 16:30:26,993 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 16:45:27,007 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 17:00:27,009 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 17:15:27,010 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 17:30:27,013 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 17:45:27,019 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 18:00:27,023 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 18:15:27,026 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 18:30:27,029 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 18:45:27,036 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 19:00:27,042 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 19:15:27,043 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 19:30:27,046 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 19:45:27,049 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 19:49:44,404 - octoprint.server.util.sockjs - INFO - New connection from client: 192.168.1.10
2018-05-16 19:49:47,265 - octoprint.plugins.announcements - INFO - Loaded channel _important from https://octoprint.org/feeds/important.xml in 0.43s
2018-05-16 19:49:47,825 - octoprint.plugins.announcements - INFO - Loaded channel _releases from https://octoprint.org/feeds/releases.xml in 0.36s
2018-05-16 19:49:48,262 - octoprint.plugins.announcements - INFO - Loaded channel _blog from https://octoprint.org/feeds/octoblog.xml in 0.35s
2018-05-16 19:49:48,775 - octoprint.plugins.announcements - INFO - Loaded channel _plugins from https://plugins.octoprint.org/feed.xml in 0.42s
2018-05-16 19:49:49,240 - octoprint.plugins.announcements - INFO - Loaded channel _octopi from https://octoprint.org/feeds/octopi.xml in 0.36s
2018-05-16 19:49:51,210 - octoprint.plugins.softwareupdate - INFO - Saved version cache to disk
2018-05-16 19:49:51,315 - octoprint.util.comm - INFO - Changing monitoring state from "Offline" to "Detecting serial port"
2018-05-16 19:49:56,651 - octoprint.util.comm - INFO - Could not enter programming mode on COM1: 'Timeout'
2018-05-16 19:49:57,283 - octoprint.util.comm - INFO - Changing monitoring state from "Detecting serial port" to "Opening serial port"
2018-05-16 19:49:57,289 - octoprint.util.comm - INFO - Changing monitoring state from "Opening serial port" to "Connecting"
2018-05-16 19:49:58,381 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2018-05-16 19:50:01,691 - octoprint.util.comm - INFO - Changing monitoring state from "Connecting" to "Operational"
2018-05-16 19:50:01,698 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2018-05-16 19:53:44,857 - octoprint.util.comm - INFO - Printer seems to support the busy protocol, telling it to set the busy interval to our "communicationBusy" timeout - 1s = 2s
2018-05-16 20:00:27,059 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 20:00:51,210 - octoprint.filemanager.analysis - INFO - Starting analysis of local:scatola_sotto.gcode
2018-05-16 20:00:51,240 - octoprint.filemanager.analysis - INFO - Invoking analysis command: C:\Octoprint\venv\Scripts\python.exe -m octoprint analysis gcode --speed-x=6000 --speed-y=6000 --max-t=10 --throttle=0.0 --throttle-lines=100 C:\Users\CENCIO\AppData\Roaming\OctoPrint\uploads\scatola_sotto.gcode
2018-05-16 20:01:00,546 - octoprint.util.comm - INFO - Changing monitoring state from "Operational" to "Printing"
2018-05-16 20:01:00,565 - octoprint.util.comm - INFO - M110 detected, setting current line number to 0
2018-05-16 20:01:00,579 - octoprint.printer.standard - INFO - Cannot load file: printer not connected or currently busy
2018-05-16 20:15:27,059 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 20:30:27,069 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 20:45:27,072 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 21:00:27,079 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 21:15:27,085 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 21:30:27,088 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 21:45:27,095 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 22:00:27,098 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 22:15:27,102 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 22:24:30,247 - octoprint.server.util.sockjs - INFO - Client connection closed: 192.168.1.10
2018-05-16 22:30:27,105 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 22:45:27,108 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 23:00:27,111 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 23:15:27,112 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 23:30:27,118 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-16 23:32:12,336 - octoprint.plugins.telegram.listener - INFO - Got a command: '/status' with parameter: '' in chat 556213450
2018-05-16 23:45:27,121 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 00:00:27,128 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 00:15:27,138 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 00:30:27,141 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 00:45:27,142 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 01:00:27,145 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 01:15:27,148 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 01:30:27,148 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 01:45:27,151 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 02:00:27,154 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 02:15:27,154 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 02:30:27,157 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 02:45:27,160 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 03:00:27,161 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 03:15:27,164 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 03:15:38,835 - octoprint.plugins.telegram.listener - ERROR - Setting status: Telegram API responded with code 502. Waiting 2 minutes before trying again.
2018-05-17 03:30:27,171 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 03:45:27,177 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 04:00:27,180 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 04:15:27,181 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 04:30:00,647 - octoprint.util.comm - ERROR - Unexpected error while reading from serial port
Traceback (most recent call last):
  File "C:\Octoprint\venv\lib\site-packages\octoprint\util\comm.py", line 2417, in _readline
    ret = self._serial.readline()
  File "C:\Octoprint\venv\lib\site-packages\octoprint\util\comm.py", line 4318, in readline
    data += bytearray(self.read(self.inWaiting())) # TODO 1.3.8 migrate to in_waiting after pyserial upgrade to 3.4
  File "c:\users\cencio\appdata\local\temp\easy_install-s9qrej\pyserial-2.7-py2.7-win32.egg.tmp\serial\serialwin32.py", line 239, in inWaiting
    raise SerialException('call to ClearCommError failed')
SerialException: call to ClearCommError failed
2018-05-17 04:30:00,684 - octoprint.util.comm - ERROR - Please see https://faq.octoprint.org/serialerror for possible reasons of this.
2018-05-17 04:30:00,703 - octoprint.util.comm - INFO - Changing monitoring state from "Printing" to "Offline (Error: SerialException: 'call to ClearCommError failed' @ comm.py:_readline:2417)"
2018-05-17 04:30:00,743 - octoprint.filemanager.analysis - INFO - Starting analysis of local:scatola_sotto.gcode
2018-05-17 04:30:00,775 - octoprint.filemanager.analysis - INFO - Invoking analysis command: C:\Octoprint\venv\Scripts\python.exe -m octoprint analysis gcode --speed-x=6000 --speed-y=6000 --max-t=10 --throttle=0.0 --throttle-lines=100 C:\Users\CENCIO\AppData\Roaming\OctoPrint\uploads\scatola_sotto.gcode
2018-05-17 04:30:27,193 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 04:31:26,263 - octoprint.filemanager.analysis - INFO - Analysis of entry local:scatola_sotto.gcode finished, needed 85.52s
2018-05-17 04:45:27,198 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 05:00:27,200 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 05:15:27,201 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 05:30:27,210 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 05:45:27,213 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 06:00:27,217 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 06:15:27,220 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 06:30:27,221 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 06:45:27,223 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 07:00:27,226 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 07:15:27,227 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 07:30:27,230 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 07:45:27,230 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 08:00:27,233 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 08:15:27,234 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 08:23:02,970 - octoprint.server.util.sockjs - INFO - New connection from client: 192.168.1.10
2018-05-17 08:30:27,253 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 08:31:27,263 - octoprint.util.comm - INFO - Changing monitoring state from "Offline" to "Detecting serial port"
2018-05-17 08:31:27,440 - octoprint.util.comm - INFO - Changing monitoring state from "Detecting serial port" to "Opening serial port"
2018-05-17 08:31:27,503 - octoprint.util.comm - INFO - Changing monitoring state from "Opening serial port" to "Connecting"
2018-05-17 08:31:57,584 - octoprint.util.comm - INFO - Changing monitoring state from "Connecting" to "Offline"
2018-05-17 08:45:27,276 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 09:00:27,280 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 09:15:27,286 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 09:16:43,834 - octoprint.server.util.sockjs - INFO - Client connection closed: 192.168.1.10
2018-05-17 09:30:27,301 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 09:45:27,312 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 10:00:27,313 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 10:15:27,318 - octoprint.server.heartbeat - INFO - Server heartbeat <3
2018-05-17 10:30:27,329 - octoprint.server.heartbeat - INFO - Server heartbeat <3

Here is the FAQ related to this (as listed in your log).

Looks like: "loose serial cable", "serial cable has internal damage", "the serial cable isn't shielded" or "the serial cable is long and therefore needs a ferrite core around it".