# Internal Server Error 400 / 403 (Clear your browser) **URL:** \ **Category:** Known Issues\ **Tags:** zbri-1761\ **Created:** [April 12, 2021, 11:47am UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438 "2021-04-12T11:47:15Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Robert\_K.Oswald](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/robert_k.oswald/32/9124_2.png) [@Robert\_K.Oswald](https://forums.zwift.com/u/Robert_K.Oswald)\ **Post date:** [April 12, 2021, 11:47am UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/1 "2021-04-12T11:47:15Z")
Anyone else unable to log onto Zwift this morning? ![Screen Shot 2021-04-12 at 7.17.30 AM](https://global.discourse-cdn.com/gozwift/original/4X/4/e/f/4ef6d53c80122054d1598fb1facbf3c4a44a352e.jpeg) ---
**Author:** ![Andreas\_Franzen3660](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/andreas_franzen3660/32/432892_2.png) [@Andreas\_Franzen3660](https://forums.zwift.com/u/Andreas_Franzen3660)\ **Post date:** [April 12, 2021, 4:28pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/2 "2021-04-12T16:28:18Z")
Similar issue here on Win10, got an error message after starting Zwift launcher ![image](https://global.discourse-cdn.com/gozwift/original/4X/0/2/6/026d0151d96017698d72f668ce016713a086d50e.png) Already reinstalled Zwift without effect.Clicking on go back to prev page does not work. In some cases the error is also HTTP 403 or 400. ---
**Author:** ![Martin\_Johnstone](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/martin_johnstone/32/56214_2.png) [@Martin\_Johnstone](https://forums.zwift.com/u/Martin_Johnstone)\ **Post date:** [April 12, 2021, 4:48pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/3 "2021-04-12T16:48:52Z")
same for me zwift on win 10 not working zwift on my android phone works fine ---
**Author:** ![Vid\_Balek](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/vid_balek/32/62945_2.png) [@Vid\_Balek](https://forums.zwift.com/u/Vid_Balek)\ **Post date:** [April 12, 2021, 4:55pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/4 "2021-04-12T16:55:11Z")
Same here. How to solve this? ---
**Author:** ![Paul\_Allen](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/paul_allen/32/414916_2.png) [@Paul\_Allen](https://forums.zwift.com/u/Paul_Allen)\ **Post date:** [April 12, 2021, 4:56pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/5 "2021-04-12T16:56:36Z")
What ISP are you guys using? More details would be helpful. ---
**Author:** ![Vid\_Balek](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/vid_balek/32/62945_2.png) [@Vid\_Balek](https://forums.zwift.com/u/Vid_Balek)\ **Post date:** [April 12, 2021, 4:57pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/6 "2021-04-12T16:57:59Z")
Not Internets fault. Works on my iPad. Looks like a login crash in IE. ---
**Author:** ![Dave\_ZPCMR](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/dave_zpcmr/32/462346_2.png) [@Dave\_ZPCMR](https://forums.zwift.com/u/Dave_ZPCMR)\ **Post date:** [April 12, 2021, 5:12pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/7 "2021-04-12T17:12:50Z")
Clear all this in Internet **Options**. ![image](https://global.discourse-cdn.com/gozwift/original/4X/a/f/6/af68481e6c2d8ec748b6f0ddeaa62c06b9f8e615.png) ---
**Author:** ![Blair\_Mac\_6456](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/blair_mac_6456/32/47767_2.png) [@Blair\_Mac\_6456](https://forums.zwift.com/u/Blair_Mac_6456)\ **Post date:** [April 12, 2021, 5:20pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/8 "2021-04-12T17:20:37Z")
Having the same issue, but getting 403 error code. was working fine this morning. Cleared cache and cookies, uninstalled and re-installed… still no joy ---
**Author:** ![B\_Steele](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/b_steele/32/432903_2.png) [@B\_Steele](https://forums.zwift.com/u/B_Steele)\ **Post date:** [April 12, 2021, 5:31pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/9 "2021-04-12T17:31:34Z")
Yes, I keep getting a 403 error. I reinstalled the app but that didn’t work. My Internet Explorer browser is working fine. I have two Windows laptops that have the same problem. This is the first time in 12 months of Zwifting that I have had this problem. ---
**Author:** ![Dave\_ZPCMR](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/dave_zpcmr/32/462346_2.png) [@Dave\_ZPCMR](https://forums.zwift.com/u/Dave_ZPCMR)\ **Post date:** [April 12, 2021, 5:39pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/10 "2021-04-12T17:39:41Z")
No issues here, checked on two systems. ---
**Author:** ![Martin\_Johnstone](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/martin_johnstone/32/56214_2.png) [@Martin\_Johnstone](https://forums.zwift.com/u/Martin_Johnstone)\ **Post date:** [April 12, 2021, 5:51pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/11 "2021-04-12T17:51:50Z")
mine seems to be working again no idea why ---
**Author:** ![Mike\_Rowe1](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/mike_rowe1/32/530428_2.png) [@Mike\_Rowe1](https://forums.zwift.com/u/Mike_Rowe1)\ **Post date:** [April 12, 2021, 5:56pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/12 "2021-04-12T17:56:41Z")
no issues here either, windows 10, location: USA ---
**Author:** ![Wouter](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/wouter/32/43144_2.png) [@Wouter](https://forums.zwift.com/u/Wouter)\ **Post date:** [April 12, 2021, 6:05pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/13 "2021-04-12T18:05:29Z")
Same problem here on Windows 10. Zwift worked fine this morning, but now I get the “HTTP 403” error. Also after a re-install. The Android version of the Zwift app (not the companion app) works fine. And when I try to chat with Community Support they simply refuse to respond. ![image](https://global.discourse-cdn.com/gozwift/original/4X/c/f/c/cfc0b7d21bc0e3f1d20e6b4733231ec94283060d.jpeg) ---
**Author:** ![Andy\_Shand](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/andy_shand/32/432907_2.png) [@Andy\_Shand](https://forums.zwift.com/u/Andy_Shand)\ **Post date:** [April 12, 2021, 6:11pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/14 "2021-04-12T18:11:52Z")
I’m getting an HTTP 403 - Windows 10 ---
**Author:** ![Vid\_Balek](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/vid_balek/32/62945_2.png) [@Vid\_Balek](https://forums.zwift.com/u/Vid_Balek)\ **Post date:** [April 12, 2021, 6:23pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/15 "2021-04-12T18:23:02Z")
cleand cookies and now it works ---
**Author:** ![Andy\_Shand](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/andy_shand/32/432907_2.png) [@Andy\_Shand](https://forums.zwift.com/u/Andy_Shand)\ **Post date:** [April 12, 2021, 7:29pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/16 "2021-04-12T19:29:04Z")
Tried clearing browser cache. No change - still getting 403. ---
**Author:** ![Matthew\_Sharman2986](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/matthew_sharman2986/32/358552_2.png) [@Matthew\_Sharman2986](https://forums.zwift.com/u/Matthew_Sharman2986)\ **Post date:** [April 12, 2021, 7:42pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/17 "2021-04-12T19:42:55Z")
I was having the same issue, clearing Internet Explorer history has fixed it - thanks, glad I found this thread. ---
**Author:** ![Andy\_Shand](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/andy_shand/32/432907_2.png) [@Andy\_Shand](https://forums.zwift.com/u/Andy_Shand)\ **Post date:** [April 12, 2021, 7:50pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/18 "2021-04-12T19:50:41Z")
After clearing Google Chrome cache/cookies, and MS Edge cache/cookies, no joy. I then cleared Internet Explorer browser history, and it’s up and running now. Looks like the browser history that needs clearing is not necessarily the browser that you actually use… Thanks for the help ---
**Author:** ![Mike\_Rowe1](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/mike_rowe1/32/530428_2.png) [@Mike\_Rowe1](https://forums.zwift.com/u/Mike_Rowe1)\ **Post date:** [April 12, 2021, 7:52pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/19 "2021-04-12T19:52:14Z")
> [@Andy\_Shand](#): > > not necessarily the browser that you actually use Zwift uses Internet Explorer, not your default browser. ---
**Author:** ![Robert\_K.Oswald](https://sea2.discourse-cdn.com/gozwift/user_avatar/forums.zwift.com/robert_k.oswald/32/9124_2.png) [@Robert\_K.Oswald](https://forums.zwift.com/u/Robert_K.Oswald)\ **Post date:** [April 12, 2021, 8:09pm UTC](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438/20 "2021-04-12T20:09:28Z")
No resolution yet but Zwift Support had me clear browser cache (I’m on a Mac so I cleared all of the ones I use), delete knowndevices.xml and prefs.xml, delete and reinstall Zwift, and perform an Internet speed test. Nothing worked. The only abnormality for me was a ping rate of 86ms to servers in Los Angeles (where Zwift told me to try), which is above the 50ms they cite on the support page. They have elevated my ticket. Once resolved I’ll post the solution. [Next page](https://forums.zwift.com/t/internal-server-error-400-403-clear-your-browser/546438.md?page=2)