> 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
Troubleshooting the sipgate fax printer on Windows - improve quality, solve connection issues.
#### 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, that is 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 the phone/fax was imported\
\- Close the fax printer if it is open and restart it via Print, fax contacts should now be loaded\
**Cause 2:** you have more than 1,000 contacts\
**Solution 2:** if possible fewer than 1,000 contacts; otherwise always enter the fax number, because search only works for up to 1,000 contacts
How can you send faxes faster?
Use this short guide to send faxes quickly:
* Send fax, wait until status "Document successfully transmitted"
* Close fax printer "click X in the top right"
* Document ➔ Print ➔ sipgate fax printer send new fax
* Check fax status in the sipgate account ➔ event list: from "Document successfully transmitted" onward, 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 occured while sending the request" when the API is blocked in the fax printer after a 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** 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 to see whether there is an error message with date and time matching the fax transmission\
**Cause:** sipgate is having an outage, API not responding\
**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 that 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 fax transmission 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 fax transmission 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**: the 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 — Object reference not set to an instance of an object
**Cause**: sipgate fax printer 3.24 is installed and can no longer be used\
**Solution**: uninstall sipgate fax printer 3.24, install the new fax printer See [Windows Apps](https://github.com/sipgate/helpcenter-gitbook/tree/main/cloud-telefonanlage/.gitbook/assets/Faxdrucker3.24Deinstallation.png)
Error: fax printer is missing from the printer list 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 and reinstall the fax printer, disable anti-virus software\
**Note 2:** "repair" did not help
Error message: "error":"unknown_error"
**Cause: default browser:** Browser cache knows the login token, does not refresh the token (Opera)\
**Solution: default browser:** Clear browser cache, fax printer login now works\
**Workaround**: Windows ➔ Default apps ➔ Browser: set a different browser, log in to the fax printer ➔ change the default browser back again\
\- 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: at Sipgate Faxdrucker.Authentication\
**Cause**: in the firewall api.sipgate.com / login.sipgate.com is allowed, but sipgate.com is blocked\
**Solution**: in the firewall allow api.sipgate.com / login.sipgate.com / sipgate.com port 443 (TLS 1.2)
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 logging in with email/password, a prompt appears; here "[Cancel](https://github.com/sipgate/helpcenter-gitbook/tree/main/cloud-telefonanlage/.gitbook/assets/ZugriffFaxErlauben.png)" was clicked\
**Solution**: log in with email/password and the fax printer [Allow access](https://github.com/sipgate/helpcenter-gitbook/tree/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 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**: Object reference 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**: Object reference 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/sipgate/helpcenter-gitbook/tree/main/cloud-telefonanlage/.gitbook/assets/OperaFirewallBlock02.png)\
**Cause**: access from the fax printer to the internet is blocked in the software firewall [Kaspersky](https://github.com/sipgate/helpcenter-gitbook/tree/main/cloud-telefonanlage/.gitbook/assets/KasperskyZugriffBlockiert.png)\
**Solution**: allow access to the internet 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 prohibited by 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 sipgate support the logs along with the fax printer login email that is affected.
Error: login data is not saved permanently
**Cause:** Software X prevents system changes or Software Y deletes config.dat\
**Problem:** Login data is deleted C://Users/"Name"/AppData/Local/sipgateFaxdrucker/config.dat\
**Example: DeepFreeze** was enabled before the fax printer login data was entered; after restarting the PC, the fax printer login data is deleted from C://Users/"Name"/AppData/Local/sipgateFaxdrucker/config.at\
**DeepFreeze solution:** Disable DeepFreeze via administrator, log in to the fax printer, set a DeepFreeze system checkpoint and enable DeepFreeze; the data should now be saved 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 change the name 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/sipgate/helpcenter-gitbook/tree/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 signed in\
\- fax printer **close**, no fax number can be entered here\
// starting it 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 is logged off 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 data cannot be found/read:**\
C:\Users\Name\AppData\Local\sipgateFaxdrucker\config.dat\
**Cause 2:** unclear, possibly anti-virus software that deletes Config.dat / moves it 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 + Windows PC user:**\
Redmon (Redirect Port Monitor) starts Faxdrucker.exe as user "SYSTEM" instead of the local user, therefore the fax printer GUI/dialog is not visible because there are not enough permissions\
**Solution for Windows 2016/2019 Server + Windows user:** Install fax printer 4.3.3.0\
**Workaround Windows 2016/2019 Server:**\
(contact a server admin or systems house for implementation)\
\- delete all sipgate fax printer registry entries if the fax printer is already installed\
\- create a local admin\
\- perform the fax printer installation with the "local admin"\
\- log in as domain admin and set all permissions under **Security** for domain users and SYSTEM\
\- the local admin can now be deleted / or you may want to delete it for security reasons\
\- the fax printer starts, needs 1-2 minutes on 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 occured while sending the request. get groupfaxlines**](https://github.com/sipgate/helpcenter-gitbook/tree/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 greyed out / not clickable**\
**Cause 1:** insufficient 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 area codes cannot be used: 0137, 0138, 01212, 01807, 0185, 0181, 0188, 0900 and 118xx\
**Cause 3:** no fax line selected / possibly the user does not have fax\
\- sipgate free has no WebFax ➔ the S/M/L plan must be used\
**Solution 3:** Select a fax line, possibly 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€ or negative credit in the sipgate account\
**Note**: despite free minutes in the trial period, you have 0€ credit\
**Solution**: none, the fax printer can only be used with credit after the trial period\
**Different**: 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 the 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 set up as a color printer, which is implemented incorrectly in at least Adobe\
**Solution: fax printer** install 4.3.3.0 / distributed via auto update\
**Windows 10 ➔** Settings ➔ Printers & scanners ➔ sipgate fax printer ➔ Manage ➔ Printing preferences ➔ Paper/Quality: save 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/sipgate/helpcenter-gitbook/tree/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 at 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 field such as signature\
**Solution:** Take a screenshot and send it via Print as fax
A local log can be found 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**: check C://Users/"Name"/AppData/Local/sipgateFaxdrucker/Logs for errors or send to sipgate support\
**Cause**:\
**Solution**:
---
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