> For the complete documentation index, see [llms.txt](https://help.sipgate.de/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.sipgate.de/cloud-telefonanlage/en/using-sipgate/fax/faxdrucker-windows-fehler-und-loesungen.md).
# Fax printer Windows: errors and solutions
#### Frequently asked questions
How can I improve the quality?
The source document should be black and white and without grayscale.
Can the fax printer be found in the Windows Store?
No, not planned for now.
Can the fax printer be installed on a Surface with an ARM CPU?
No, the fax printer only works with x86/x64 Intel/AMD CPUs
Is the upload of the temporary fax PDF encrypted?
From the fax printer to the web server, the data is transmitted encrypted via SSL port 443 using TLS 1.2.
Why can't I see any contacts?
**Cause 1:** you only have phone contacts\
**Solution 1:**\
\- Import contacts via Google/CSV, make sure that phone/fax was imported\
\- If open, close the fax printer and restart via Print; fax contacts should now be loaded\
**Cause 2:** you have more than 1000 contacts\
**Solution 2:** if possible fewer than 1000 contacts; otherwise always enter the fax number, since search only works for up to 1000 contacts
How can you send faxes faster?
Use this quick guide to send faxes quickly:
* Send fax, wait until status "Document successfully transmitted"
* Close the fax printer "click the X in the top right"
* Document ➔ Print ➔ sipgate fax printer send a new fax
* Check the fax status in the sipgate account ➔ event list; from "Document successfully transmitted" the PDF is on the sipgate server, which then sends the fax. You only need to wait in the fax printer if you want to see the transmission status through to the end.
#### Possible error codes
Below you will find a brief explanation of certain error codes
F400 "Transmission failed, please try again later (F400)
**Log:** "failed to send fax: An error occurred while sending the request" when the API is blocked in the fax printer after successful login\
**Cause:** Software firewall blocks requests from the fax printer to our API [https://api.sipgate.com](https://api.sipgate.com/) 217.10.72.56 and [https://login.sipgate.com](https://login.sipgate.com/) **or** the internet in general\
**Solution:** allow the fax printer to access the network/internet in the software/router firewall\
**Approach**: check C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs for an error message with date and time matching the fax sending\
**Cause:** sipgate is experiencing an outage, API does not respond\
**Solution:** Status website: check and wait
Login works, fax line loaded, error when sending (F400)
**Log:** "Error: 0 : Failed! Response code was: GatewayTimeout" and "Warning: 400 : Sending failed: Api returned no sessionId"\
**Cause:** api.sipgate.com cannot be reached\
**Solution:** Check in the firewall rules whether api.sipgate.com / 217.10.72.56 is temporarily blocked
Make sure you have an internet connection.
\*\*Cause:\*\* there is no internet connection when sending a fax\
**Solution:** Check and repair the internet connection, then resend the fax
F500: The transmission of the fax to our systems failed for an unknown reason.
Please contact customer support, ideally with a description of how to reproduce the behavior.
F413: The transmission of the fax failed because the file is larger than 9 MB.
The transmission of the fax to our systems failed because the file is larger than 9 MB.
F415: The transmission of the fax failed because the file is invalid.
The transmission of the fax to our systems failed because the file is invalid. Try a different file type.
#### Possible errors and solutions
Error message: The application requires .Net Framework 4.6.1 (4.3.2.0)
**Cause**: You are using Windows 7 Service Pack 1 without .Net Framework 4.6.1\
**Solution**: Download and install .Net Framework 4.6.1 for Windows 7 from Microsoft [Link](https://www.microsoft.com/de-de/download/details.aspx?id=49982)\
**Note**: fax printer 4.2+ cannot be used on Windows 7
Error message: The application requires .Net Framework 4.6.2 (4.3.3.0)
**Cause**: Windows 7/8 is missing .Net Framework 4.6.2, which is required by the fax printer\
**Solution**: [.Net Framework 4.6.2](https://support.microsoft.com/de-de/topic/das-net-framework-4-6-2-offlineinstallationsprogramm-f%C3%BCr-windows-9dce3874-a9e5-9b11-289d-5594824aafe0) install it, the fax printer installation should now work
Error message: FaxUI — The object reference was not set to an instance of an object
**Cause**: sipgate Faxdrucker 3.24 is installed and can no longer be used\
**Solution**: uninstall sipgate Faxdrucker 3.24, install the new fax printer See [Windows Apps](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/Faxdrucker3.24Deinstallation.png)
Error: fax printer is missing from the printer overview after installation
**Cause 1**: Task Manager ➔ Services ➔ Spooler "Print queue" ➔ Stopped\
**Solution 1**: Task Manager ➔ Services ➔ Spooler "Print queue" ➔ right-click "Start\
**Cause 2:** Anti-virus software has blocked a registry entry\
**Solution 2:** Uninstall the fax printer, reinstall it, disable the anti-virus software\
**Note 2:** "repair" did not help
Error message: "error":"unknown_error"
**Cause standard browser:** Browser cache knows the login token, does not renew the token (Opera)\
**Solution standard browser:** Clear browser cache, fax printer login now works\
**Workaround**: Windows ➔ Default Apps ➔ Browser: set a different browser, log into the fax printer ➔ change back to the original default browser\
\- Logout/login now also works with the previous default browser
Error message: "Authentication not possible." / Login failed!
**Analyze log:** C://Users/"Name"/AppData/Local/sipgate Faxdrucker/Logs\
\- sipgate Faxdrucker Critical: 0 : Could not perform code exchange: The remote server returned an error: (407) Proxy authentication required.\
\- sipgate Faxdrucker Critical: 0 : Could not perform code exchange: in Sipgate Faxdrucker.Authentication\
**Cause**: in the firewall api.sipgate.com / login.sipgate.com are allowed, but sipgate.com is blocked\
**Solution**: allow api.sipgate.com / login.sipgate.com / sipgate.com port 443 (TLS 1.2) in the firewall
Error message: Login failed! / Error during login
**Analyze log:** C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs\
\- sipgateFaxdrucker Critical: 0 : Error Authenticating: access\_denied\
**Cause**: after login with email/password, a prompt appears, here was "[Cancel](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/ZugriffFaxErlauben.png)" clicked\
**Solution**: log in with email/password and the fax printer [Allow access](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/ZugriffFaxErlauben.png)
Error: when clicking "log in in browser" + "No internet"
**Firefox**: "Page not found"\
**Opera**: "No internet"\
**Chrome**: "The website can't be reached"\
**Cause:** no internet / network cable not connected, etc.\
**Solution:** Connect the internet / network cable
Error: when clicking "log in in browser" + "No connection/failed"
**Firefox:** Firefox cannot establish a connection to the server at 127.0.0.1:51007\
\
**Firefox + sipgate cookie**: The object reference was not set to an instance of an object. [Image](https://sipgate.zendesk.com/knowledge/articles/211585785/de?brand_id=559261\&return_to=%2Fhc%2Fde%2Farticles%2F211585785)\
**Firefox without sipgate cookie**: Error: connection failed\
**Chrome**: Your internet connection is blocked\
**Edge Chromium:** Your internet access is blocked\
**Opera**: The object reference was not set to an instance of an object. [Image](https://sipgate.zendesk.com/knowledge/articles/211585785/de?brand_id=559261\&return_to=%2Fhc%2Fde%2Farticles%2F211585785)\
**Opera**: The website can't be reached 127.0.0.1 refused the connection [Image](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/OperaFirewallBlock02.png)\
**Cause**: in the software firewall, access from the fax printer to the internet is blocked [Kaspersky](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/KasperskyZugriffBlockiert.png)\
**Solution**: allow internet access in the software firewall
Error: clicking "log in in browser" does not open the browser
C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs\
[System.Net](http://system.net/).Sockets.SocketException: Access to a socket was denied because of the socket's access permissions 217.10.72.54:443\
**Cause 1**: Windows ➔ Outbound rules ➔ sipgate fax printer rule blocking IP 217.10.72.54\
**Solution 1**: Windows ➔ Outbound rules ➔ delete the sipgate fax printer rule or allow access\
**Analyze logs:**\
sipgateFaxdrucker Warning: 0 : Did not fetch balance due to missing access rights: Balance endpoint returned 403: Forbidden for this user\
**Cause 2**: unclear\
**Solution 2**: send support logs to sipgate, including the fax printer login email affected.
Error: login credentials are not stored permanently
**Cause:** Software X prevents system changes or software Y deletes config.dat\
**Problem:** Login credentials are deleted C://Users/"Name"/AppData/Local/sipgateFaxdrucker/config.dat\
**Example: DeepFreeze** was activated before fax printer login credentials were entered; after restarting the PC, fax printer login credentials are deleted from C://Users/"Name"/AppData/Local/sipgateFaxdrucker/config.at\
**DeepFreeze solution:** Disable DeepFreeze via administrator, log into the fax printer, set the DeepFreeze system point, and activate DeepFreeze; the data should now be stored permanently\
**Example: McAfee Anti-Virus:** Scan drive C:// and check whether McAfee deleted config.dat\
**McAfee Anti-Virus solution:** restore config.dat and mark it as trusted
Error: Windows print job reports "Error printing" — the print job deletes itself
"Document.pdf" could not be printed by the printer.\
**Cause**: the fax printer is uninstalled; there is only a renamed fax printer entry left\
**Solution**: Windows ➔ Printers ➔ delete the renamed printer entry "Remove device"\
\- Install the fax printer, optionally rename it back to sipgate-Faxdrucker
Error: print job ends up in the print queue / fax printer does not open (user)
**Analysis 1: Windows 10/11 + user**: fax printer starts as [process](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/ProzessFaxdrucker.png) but not as user\
**Solution 1 Windows 10/11 user**: install fax printer 4.3.3.0\
**Workaround 1 Windows 10/11 + user**:\
\- Cancel the print job if present\
Start C:/Program Files/sipgateFaxdrucker/sipgateFaxdrucker.exe, log in to sipgate; the fax printer should now be logged in\
\- Fax printer **close**, here no fax number can be entered\
// starting once is necessary to obtain "user rights"\
\- Document ➔ Print ➔ Fax printer ➔ the fax printer now opens, enter fax number\
\- restart sipgateFaxdrucker.exe manually when the user logs out or the PC is restarted\
**Analysis 2:** %LocalAppData%\sipgateFaxdrucker\Logs\
Log error: sipgateFaxdrucker Critical: 0 : error loading credentials: The array cannot be NULL\
**Problem 2: login credentials cannot be found/read:**\
C:\Users\Name\AppData\Local\sipgateFaxdrucker\config.dat\
**Cause 2:** unclear, possibly anti-virus software that deletes/moves config.dat to quarantine\
**Solution 2:** unclear, check antivirus/firewall
Error: print job ends up in the print queue / fax printer does not open (Windows Server)
**Cause Windows 2016/2019 Server + WinPC user:**\
Redmon (Redirect Port Monitor) starts Faxdrucker.exe as user "SYSTEM" instead of the local user, so the fax printer GUI/dialog is not visible because there are not enough permissions\
**Solution Windows 2016/2019 Server + Windows user:** Install fax printer 4.3.3.0\
**Workaround Windows 2016/2019 Server:**\
(contact a server admin or IT service provider to implement)\
\- delete all sipgate fax printer registry entries if the fax printer is already installed\
\- create a local admin\
\- perform the fax printer installation with "local admin"\
\- log in as domain admin and set all rights under **Security** for domain users and SYSTEM\
\- local admin can now be deleted / or if you want to delete it for security reasons\
\- fax printer starts, needs 1-2 min on the first start, then starts faster
Error: fax line is empty + no contacts found + "Send fax" is greyed out
**Error: when clicking "fax line" /** [**get groupfaxlines An error occurred while sending the request. get groupfaxlines**](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/ErrorOccuredWhileSendingRequest.png)\
**Cause 0**: software/hardware firewall blocks requests to api.sipgate.com\
**Solution 0**: allow access to api.sipgate.com in the software/hardware firewall\
**Example**.: Fritz Box ➔ Internet ➔ Filter ➔ Lists ➔ Blocked websites [edit ➔](http://192.168.178.1/#/) api.sipgate.com\
**Example**.: Kaspersky ➔ Settings ➔ Protection ➔ Firewall ➔ Packet rules ➔ custom rule that blocks api.sipgate.com / 217.10.72.56\
**Example**.: C:\Windows\System32\drivers\etc\hosts entry 127.0.0.1 api.sipgate.com\
\&#xNAN;**"Send fax" button is still grey / not clickable**\
**Cause 1:** not enough credit\
**Solution 1:** top up credit\
**Cause 2:** invalid fax number entered\
**Solution 2:** Check whether the fax number is entered correctly / no special characters\
The following prefixes cannot be used: 0137, 0138, 01212, 01807, 0185, 0181, 0188, 0900 and 118xx\
**Cause 3:** no fax line selected / the user may not have a fax\
\- sipgate free has no WebFax ➔ the S/M/L plan must be used\
**Solution 3:** Select a fax line, if necessary switch to an S/M/L plan\
**Cause 4:** unclear\
**Approach 4:** Check C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs / send to support\
**Solution 4:** unclear
Error: Your credit is insufficient. (at least 1.79 ct)
**Cause**: you should not have 0€ credit or negative credit in the sipgate account\
**Note**: despite free minutes in the trial phase, you have 0€ credit\
**Solution**: no, the fax printer can only be used with credit after the trial phase\
**Exception**: use WebFax, the WebFax in the customer area can use free minutes and credit
Error: fax printer login menu does not open after about 1 min "printed file is too large"
**Description**: fax printer is listed among printers; when printing Document->Fax printer, the login menu does not open, after 1 min an error message appears: file too large\
**Cause**: file is larger than 9 MB\
**Solution**: reduce the file size
Error: black/white document is sent as a black background + red text
**Cause:** the fax printer is configured as a color printer, which is implemented incorrectly in at least Adobe\
**Solution: fax printer** install 4.3.3.0 / is distributed via auto update\
**Windows 10 ➔** Settings ➔ Printers & scanners ➔ sipgate fax printer ➔ Manage ➔ Print settings ➔ Paper/Quality: save as black-and-white printer\
**Windows 11 ➔** Settings ➔ Bluetooth & devices ➔ Printers & scanners ➔ sipgate fax printer ➔ Printer settings ➔ Paper/Quality ➔ Black and white\
**Cause Adobe Acrobat Reader:** Print ➔ Fax printer: "Save color/toner" enabled [Image\_01](https://github.com/pinekenstein/zendesk-import/blob/main/cloud-telefonanlage/.gitbook/assets/AdobeReaderFarbe.png)\
**Solution Adobe Acrobat Reader:** Print ➔ Fax printer ➔ "in grayscale (black and white)
Error: "ghostscript errorSystem.Runtime.InteropServices.ExternalExeption (0xFFFFFF9C): Ghostscript conversion error in SipgateFaxdrucker.GhostScript.GhostScript64.CallApi(String[] args) in \GhostScript64.cs:line 32"
**Problem:** the Ghostscript in the fax printer cannot convert the document to PDF\
**Cause:** Adobe PDF with form fields such as signature\
**Solution:** Take a screenshot and send it as a fax via Print
You can find a local log here: C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs\
**Examples:**\
Error: 0 : No credential Manager found\
Warning: 0 : Refreshing token failed\
sipgateFaxdrucker Critical: 0 : error loading credentials: The array cannot be NULL
Error: "The operation is not supported on this platform"
**Analysis**: C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs\
check for errors or send to sipgate support\
**Cause**:\
**Solution**:
---
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