Reviews of mail.com MailCheck

By: 1&1 Mail & Media GmbH Add-on

List of user reviews and ratings for mail.com MailCheck

Total ratings

2.67 (Rating count: 83)

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Review summary

Recurring issues across reviews show the Firefox version of mail.com MailCheck is unreliable: many users cannot log in, experience Firefox-specific compatibility problems, and cannot add accounts, with some privacy concerns raised about data telemetry. The lack of consistent developer support is also noted.

Pros

Cons

Frequent login failures on Firefox: login button inactive or sign-in process hangs.
Firefox compatibility issues: reports that the extension works in Chrome but not in Firefox, with compatibility warnings.
Account setup flow is broken in Firefox: users cannot add new accounts and password input may be missing or blocked.
Privacy concerns: reports of telemetry and data collection/sharing.

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User Reviews

Recent rating average: 2.40

All time rating average: 2.67

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49% (43)

Date	Author	Comment
2026-08-08	Al*****	No outlook support gives error: "We are sorry, this email provider is currently not supported." please update this app it works perfectly fine on chrome and edge, but firefox and other firefox forks are giving this error when trying to add an outlook email address.
No outlook support gives error: "We are sorry, this email provider is currently not supported." please update this app it works perfectly fine on chrome and edge, but firefox and other firefox forks are giving this error when trying to add an outlook email address.
2026-07-07	Fi*****	erreur statut-code "403" message "bloqué" requête-id "d2a19740d73acfe2c4072b056ba33039"
erreur statut-code "403" message "bloqué" requête-id "d2a19740d73acfe2c4072b056ba33039"
2026-07-05	Ri*****	it's ok
it's ok
2025-11-17	Co*****	Doesn't work. Initial login/setup on desktop Firefox doesn't work. Error in browser console when trying submit email for login: "Uncaught Error: error_permission" at onboarding-panel.js:9330:99
Doesn't work. Initial login/setup on desktop Firefox doesn't work. Error in browser console when trying submit email for login: "Uncaught Error: error_permission" at onboarding-panel.js:9330:99
2025-09-21	Au*****	Extension works good for me once you set It up It will appear to not work but If you click on the mail.com extension It will show your account & you have the option to set up another.
Extension works good for me once you set It up It will appear to not work but If you click on the mail.com extension It will show your account & you have the option to set up another.
2025-09-04	Mr*****	Doesn't work anymore, can't login.
Doesn't work anymore, can't login.
2025-07-25	Ku*****	Doesn't work anymore with there own domains, gmail.com and outlook.com works for this mail check extension but not their own like email.com, mail.com, gmx.com; what a fucking joke. I contacted the developer several times, he never responded even the support said to use another browser, contacted them through email twitter and they fucking never responded. I am a paying customer to their service, recently switched to firefox and this is how they treat us
Doesn't work anymore with there own domains, gmail.com and outlook.com works for this mail check extension but not their own like email.com, mail.com, gmx.com; what a fucking joke. I contacted the developer several times, he never responded even the support said to use another browser, contacted them through email twitter and they fucking never responded. I am a paying customer to their service, recently switched to firefox and this is how they treat us
2025-07-17	G_*****	If you check the necessary permissions, you will realize that there is a lot of telemetry and sharing of your browsing data.
If you check the necessary permissions, you will realize that there is a lot of telemetry and sharing of your browsing data.
2025-02-13	天灭*****

2024-12-21	Fi*****