hello, could you go to the firefox menu ≡ > help ? > troubleshooting information, copy the contents of that page and paste them here into a reply on the forum? this might give us a clue what is going on...

Here's the copied text (1 of 3):

Application Basics

Name: Firefox Version: 40.0.3 Build ID: 20150826023504 Update Channel: release User Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0 Multiprocess Windows: 0/1 (default: false)

Crash Reports for the Last 3 Days

All Crash Reports

Extensions

Name: Adblock Plus Version: 2.6.10 Enabled: true ID: {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}

Name: Browser Manager Version: 0.13 Enabled: true ID: {ae865166-ab36-45f8-be8f-70abd02a9f6d}

Name: Clearly Version: 10.2.1.7.1-signed Enabled: true ID: readable@evernote.com

Name: ColorZilla Version: 2.8.2 Enabled: true ID: {6AC85730-7D0F-4de0-B3FA-21142DD85326}

Name: Firebug Version: 2.0.12 Enabled: true ID: firebug@software.joehewitt.com

Name: FireGestures Version: 1.10.1 Enabled: true ID: firegestures@xuldev.org

Name: Flash and Video Download Version: 1.76 Enabled: true ID: {bee6eb20-01e0-ebd1-da83-080329fb9a3a}

Name: Nimbus Screen Capture - editable screenshots. Version: 6.6.1 Enabled: true ID: nimbusscreencaptureff@everhelper.me

Name: RememberPass Version: 1.1.2.1-signed Enabled: true ID: rememberpass@teesoft.info

Name: YouTube Unblocker Version: 0.6.17 Enabled: true ID: youtubeunblocker@unblocker.yt

Name: Browser Guard Version: 0.2 Enabled: false ID: {20d1f7b3-7721-4da0-b6f3-78bb4d7248f4}

Name: Freemake Video Converter Plugin Version: 1.0.0 Enabled: false ID: fmconverter@gmail.com

Name: Lightbeam Version: 1.2.1.1-signed Enabled: false ID: jid1-F9UJ2thwoAm5gQ@jetpack

Name: Logitech SetPoint Version: 6.5 Enabled: false ID: {F003DA68-8256-4b37-A6C4-350FA04494DF}

Name: NetVideoHunter Version: 1.18 Enabled: false ID: netvideohunter@netvideohunter.com

Name: PDF Architect 3 Creator Version: 1.0 Enabled: false ID: pdf_architect_3_conv@pdfarchitect.org

Graphics

Adapter Description: AMD Radeon HD 6800 Series Adapter Drivers: aticfx64 aticfx64 aticfx64 amdxc64 aticfx32 aticfx32 aticfx32 amdxc32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64 Adapter RAM: 1024 Asynchronous Pan/Zoom: none ClearType Parameters: Gamma: 2200 Pixel Structure: R ClearType Level: 100 Enhanced Contrast: 200 Device ID: 0x6738 Direct2D Enabled: true DirectWrite Enabled: true (10.0.10240.16430) Driver Date: 8-3-2015 Driver Version: 15.200.1062.1004 GPU #2 Active: false GPU Accelerated Windows: 1/1 Direct3D 11 (OMTC) Subsys ID: 174b174b Supports Hardware H264 Decoding: true Vendor ID: 0x1002 WebGL Renderer: Google Inc. -- ANGLE (AMD Radeon HD 6800 Series Direct3D11 vs_5_0 ps_5_0) windowLayerManagerRemote: true AzureCanvasBackend: direct2d 1.1 AzureContentBackend: direct2d 1.1 AzureFallbackCanvasBackend: cairo AzureSkiaAccelerated: 0

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Important Modified Preferences

accessibility.typeaheadfind: true accessibility.typeaheadfind.flashBar: 0 accessibility.warn_on_browsewithcaret: false browser.cache.disk.capacity: 358400 browser.cache.disk.filesystem_reported: 1 browser.cache.disk.smart_size_cached_value: 358400 browser.cache.disk.smart_size.first_run: false browser.cache.disk.smart_size.use_old_max: false browser.cache.frecency_experiment: 1 browser.download.importedFromSqlite: true browser.download.manager.closeWhenDone: true browser.download.manager.retention: 0 browser.download.useDownloadDir: false browser.places.smartBookmarksVersion: 7 browser.search.useDBForOrder: true browser.sessionstore.upgradeBackup.latestBuildID: 20150826023504 browser.startup.homepage: about:home browser.startup.homepage_override.buildID: 20150826023504 browser.startup.homepage_override.mstone: 40.0.3 browser.tabs.loadInBackground: false browser.tabs.warnOnClose: false browser.zoom.full: false dom.apps.reset-permissions: true dom.max_chrome_script_run_time: 0 dom.max_script_run_time: 0 dom.mozApps.maxLocalId: 1002 dom.mozApps.runUpdate: false dom.mozApps.used: true dom.mozTCPSocket.enabled: true dom.w3c_touch_events.enabled: 1 dom.w3c_touch_events.expose: false extensions.lastAppVersion: 40.0.3 font.default.x-western: sans-serif font.name.monospace.x-western: Consolas font.name.sans-serif.x-western: Calibri font.name.serif.x-western: Consolas font.size.variable.x-central-euro: 18 gfx.direct3d.last_used_feature_level_idx: 0 gfx.direct3d.prefer_10_1: true media.gmp-eme-adobe.lastUpdate: 1434383810 media.gmp-eme-adobe.version: 11 media.gmp-gmpopenh264.lastUpdate: 1431715438 media.gmp-gmpopenh264.path: C:\Users\Peter\AppData\Roaming\Mozilla\Firefox\Profiles\764ai7g2.default\gmp-gmpopenh264 media.gmp-gmpopenh264.version: 1.4 media.gmp-manager.buildID: 20150826023504 media.gmp-manager.lastCheck: 1435256655 network.cookie.prefsMigrated: true network.http.max-persistent-connections-per-server: 4 network.predictor.cleaned-up: true places.database.lastMaintenance: 1442603292 places.history.expiration.transient_current_max_pages: 104858 plugin.disable_full_page_plugin_for_types: application/pdf plugin.importedState: true print.printer_Adobe_PDF.print_bgcolor: false print.printer_Adobe_PDF.print_bgimages: false print.printer_Adobe_PDF.print_colorspace: print.printer_Adobe_PDF.print_command: print.printer_Adobe_PDF.print_downloadfonts: false print.printer_Adobe_PDF.print_duplex: 3473475 print.printer_Adobe_PDF.print_edge_bottom: 0 print.printer_Adobe_PDF.print_edge_left: 0 print.printer_Adobe_PDF.print_edge_right: 0 print.printer_Adobe_PDF.print_edge_top: 0 print.printer_Adobe_PDF.print_evenpages: true print.printer_Adobe_PDF.print_footercenter: &PT print.printer_Adobe_PDF.print_footerleft: print.printer_Adobe_PDF.print_footerright: &D print.printer_Adobe_PDF.print_headercenter: print.printer_Adobe_PDF.print_headerleft: &U print.printer_Adobe_PDF.print_headerright: print.printer_Adobe_PDF.print_in_color: true print.printer_Adobe_PDF.print_margin_bottom: 0.393750011920929 print.printer_Adobe_PDF.print_margin_left: 0.196527779102325 print.printer_Adobe_PDF.print_margin_right: 0.196527779102325 print.printer_Adobe_PDF.print_margin_top: 0.393750011920929 print.printer_Adobe_PDF.print_oddpages: true print.printer_Adobe_PDF.print_orientation: 0 print.printer_Adobe_PDF.print_page_delay: 50 print.printer_Adobe_PDF.print_paper_data: 9 print.printer_Adobe_PDF.print_paper_height: 11,00 print.printer_Adobe_PDF.print_paper_name: print.printer_Adobe_PDF.print_paper_size_type: 0 print.printer_Adobe_PDF.print_paper_size_unit: 1 print.printer_Adobe_PDF.print_paper_width: 8,50 print.printer_Adobe_PDF.print_plex_name: print.printer_Adobe_PDF.print_resolution: 6619244 print.printer_Adobe_PDF.print_resolution_name: print.printer_Adobe_PDF.print_reversed: false print.printer_Adobe_PDF.print_scaling: 1,00 print.printer_Adobe_PDF.print_shrink_to_fit: false print.printer_Adobe_PDF.print_to_file: false print.printer_Adobe_PDF.print_unwriteable_margin_bottom: 0 print.printer_Adobe_PDF.print_unwriteable_margin_left: 0 print.printer_Adobe_PDF.print_unwriteable_margin_right: 0 print.printer_Adobe_PDF.print_unwriteable_margin_top: 0 print.printer_Canon_MG5400_series_Printer.print_bgcolor: false print.printer_Canon_MG5400_series_Printer.print_bgimages: false print.printer_Canon_MG5400_series_Printer.print_colorspace: print.printer_Canon_MG5400_series_Printer.print_command: print.printer_Canon_MG5400_series_Printer.print_downloadfonts: false print.printer_Canon_MG5400_series_Printer.print_duplex: 3473475 print.printer_Canon_MG5400_series_Printer.print_edge_bottom: 0 print.printer_Canon_MG5400_series_Printer.print_edge_left: 0 print.printer_Canon_MG5400_series_Printer.print_edge_right: 0 print.printer_Canon_MG5400_series_Printer.print_edge_top: 0 print.printer_Canon_MG5400_series_Printer.print_evenpages: true print.printer_Canon_MG5400_series_Printer.print_footercenter: print.printer_Canon_MG5400_series_Printer.print_footerleft: &PT print.printer_Canon_MG5400_series_Printer.print_footerright: &D print.printer_Canon_MG5400_series_Printer.print_headercenter: print.printer_Canon_MG5400_series_Printer.print_headerleft: &T print.printer_Canon_MG5400_series_Printer.print_headerright: &U print.printer_Canon_MG5400_series_Printer.print_in_color: true print.printer_Canon_MG5400_series_Printer.print_margin_bottom: 0.5 print.printer_Canon_MG5400_series_Printer.print_margin_left: 0.5 print.printer_Canon_MG5400_series_Printer.print_margin_right: 0.5 print.printer_Canon_MG5400_series_Printer.print_margin_top: 0.5 print.printer_Canon_MG5400_series_Printer.print_oddpages: true print.printer_Canon_MG5400_series_Printer.print_orientation: 0 print.printer_Canon_MG5400_series_Printer.print_page_delay: 50 print.printer_Canon_MG5400_series_Printer.print_paper_data: 9 print.printer_Canon_MG5400_series_Printer.print_paper_height: 11,00 print.printer_Canon_MG5400_series_Printer.print_paper_name: print.printer_Canon_MG5400_series_Printer.print_paper_size_type: 0 print.printer_Canon_MG5400_series_Printer.print_paper_size_unit: 1 print.printer_Canon_MG5400_series_Printer.print_paper_width: 8,50 print.printer_Canon_MG5400_series_Printer.print_plex_name: print.printer_Canon_MG5400_series_Printer.print_resolution: 6619244 print.printer_Canon_MG5400_series_Printer.print_resolution_name: print.printer_Canon_MG5400_series_Printer.print_reversed: false print.printer_Canon_MG5400_series_Printer.print_scaling: 0,50 print.printer_Canon_MG5400_series_Printer.print_shrink_to_fit: false print.printer_Canon_MG5400_series_Printer.print_to_file: false print.printer_Canon_MG5400_series_Printer.print_unwriteable_margin_bottom: 0 print.printer_Canon_MG5400_series_Printer.print_unwriteable_margin_left: 0 print.printer_Canon_MG5400_series_Printer.print_unwriteable_margin_right: 0 print.printer_Canon_MG5400_series_Printer.print_unwriteable_margin_top: 0 print.printer_Canon_MX920_series_Printer.print_bgcolor: false print.printer_Canon_MX920_series_Printer.print_bgimages: false print.printer_Canon_MX920_series_Printer.print_colorspace: print.printer_Canon_MX920_series_Printer.print_command: print.printer_Canon_MX920_series_Printer.print_downloadfonts: false print.printer_Canon_MX920_series_Printer.print_duplex: 3473475 print.printer_Canon_MX920_series_Printer.print_edge_bottom: 0 print.printer_Canon_MX920_series_Printer.print_edge_left: 0 print.printer_Canon_MX920_series_Printer.print_edge_right: 0 print.printer_Canon_MX920_series_Printer.print_edge_top: 0 print.printer_Canon_MX920_series_Printer.print_evenpages: true print.printer_Canon_MX920_series_Printer.print_footercenter: &PT print.printer_Canon_MX920_series_Printer.print_footerleft: print.printer_Canon_MX920_series_Printer.print_footerright: &D print.printer_Canon_MX920_series_Printer.print_headercenter: print.printer_Canon_MX920_series_Printer.print_headerleft: &U print.printer_Canon_MX920_series_Printer.print_headerright: print.printer_Canon_MX920_series_Printer.print_in_color: true print.printer_Canon_MX920_series_Printer.print_margin_bottom: 0.393750011920929 print.printer_Canon_MX920_series_Printer.print_margin_left: 0.196527779102325 print.printer_Canon_MX920_series_Printer.print_margin_right: 0.196527779102325 print.printer_Canon_MX920_series_Printer.print_margin_top: 0.393750011920929 print.printer_Canon_MX920_series_Printer.print_oddpages: true print.printer_Canon_MX920_series_Printer.print_orientation: 1 print.printer_Canon_MX920_series_Printer.print_page_delay: 50 print.printer_Canon_MX920_series_Printer.print_paper_data: 9 print.printer_Canon_MX920_series_Printer.print_paper_height: 11,00 print.printer_Canon_MX920_series_Printer.print_paper_name: print.printer_Canon_MX920_series_Printer.print_paper_size_type: 0 print.printer_Canon_MX920_series_Printer.print_paper_size_unit: 1 print.printer_Canon_MX920_series_Printer.print_paper_width: 8,50 print.printer_Canon_MX920_series_Printer.print_plex_name: print.printer_Canon_MX920_series_Printer.print_resolution: 6619244 print.printer_Canon_MX920_series_Printer.print_resolution_name: print.printer_Canon_MX920_series_Printer.print_reversed: false print.printer_Canon_MX920_series_Printer.print_scaling: 1,00 print.printer_Canon_MX920_series_Printer.print_shrink_to_fit: false print.printer_Canon_MX920_series_Printer.print_to_file: false print.printer_Canon_MX920_series_Printer.print_unwriteable_margin_bottom: 0 print.printer_Canon_MX920_series_Printer.print_unwriteable_margin_left: 0 print.printer_Canon_MX920_series_Printer.print_unwriteable_margin_right: 0 print.printer_Canon_MX920_series_Printer.print_unwriteable_margin_top: 0

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print.printer_PDFCreator.print_bgcolor: false print.printer_PDFCreator.print_bgimages: false print.printer_PDFCreator.print_colorspace: print.printer_PDFCreator.print_command: print.printer_PDFCreator.print_downloadfonts: false print.printer_PDFCreator.print_duplex: 3473475 print.printer_PDFCreator.print_edge_bottom: 0 print.printer_PDFCreator.print_edge_left: 0 print.printer_PDFCreator.print_edge_right: 0 print.printer_PDFCreator.print_edge_top: 0 print.printer_PDFCreator.print_evenpages: true print.printer_PDFCreator.print_footercenter: &PT print.printer_PDFCreator.print_footerleft: print.printer_PDFCreator.print_footerright: &D print.printer_PDFCreator.print_headercenter: print.printer_PDFCreator.print_headerleft: &U print.printer_PDFCreator.print_headerright: print.printer_PDFCreator.print_in_color: true print.printer_PDFCreator.print_margin_bottom: 0.393750011920929 print.printer_PDFCreator.print_margin_left: 0.196527779102325 print.printer_PDFCreator.print_margin_right: 0.196527779102325 print.printer_PDFCreator.print_margin_top: 0.393750011920929 print.printer_PDFCreator.print_oddpages: true print.printer_PDFCreator.print_orientation: 0 print.printer_PDFCreator.print_page_delay: 50 print.printer_PDFCreator.print_paper_data: 9 print.printer_PDFCreator.print_paper_height: 11,00 print.printer_PDFCreator.print_paper_name: print.printer_PDFCreator.print_paper_size_type: 0 print.printer_PDFCreator.print_paper_size_unit: 1 print.printer_PDFCreator.print_paper_width: 8,50 print.printer_PDFCreator.print_plex_name: print.printer_PDFCreator.print_resolution: 6619244 print.printer_PDFCreator.print_resolution_name: print.printer_PDFCreator.print_reversed: false print.printer_PDFCreator.print_scaling: 1,00 print.printer_PDFCreator.print_shrink_to_fit: false print.printer_PDFCreator.print_to_file: false print.printer_PDFCreator.print_unwriteable_margin_bottom: 0 print.printer_PDFCreator.print_unwriteable_margin_left: 0 print.printer_PDFCreator.print_unwriteable_margin_right: 0 print.printer_PDFCreator.print_unwriteable_margin_top: 0 privacy.cpd.offlineApps: true privacy.cpd.sessions: false privacy.donottrackheader.enabled: true privacy.sanitize.migrateFx3Prefs: true privacy.sanitize.timeSpan: 2 security.disable_button.openCertManager: false security.warn_viewing_mixed: false storage.vacuum.last.index: 1 storage.vacuum.last.places.sqlite: 1440606237

user.js Preferences

Your profile folder contains a user.js file, which includes preferences that were not created by Firefox.

Important Locked Preferences

JavaScript

Incremental GC: true

Accessibility

Activated: false Prevent Accessibility: 0

Library Versions

NSPR Expected minimum version: 4.10.8 Version in use: 4.10.8

NSS Expected minimum version: 3.19.2 Basic ECC Version in use: 3.19.2 Basic ECC

NSSSMIME Expected minimum version: 3.19.2 Basic ECC Version in use: 3.19.2 Basic ECC

NSSSSL Expected minimum version: 3.19.2 Basic ECC Version in use: 3.19.2 Basic ECC

NSSUTIL Expected minimum version: 3.19.2 Version in use: 3.19.2

Experimental Features

Name: Invisible test of the experiment branching system. ID: experiment-branch-test-nightly@experiments.mozilla.org Description: An experiment using branches just to test whether branches get saved correctly. Active: false End Date: 1409598829069 Homepage:

thank you, there are a couple of issues that stick out from it:

• the "Browser Manager 0.13" extension appears to be bogus, please go to the firefox menu ≡ > addons > extensions & remove it
• you have a user.js file in your profile which shouldn't be there unless you've manually created it, because it will be used (often by malicious software) to overwride your custom settings. go to the firefox menu ≡ > help ? > troubleshooting information > profile folder - "show folder", then a new window will open up. in this window look out for a file named user.js and remove it.
• enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named network.http.max-persistent-connections-per-server - right-click and reset that entry to the default value.