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Forum Discussion
Reidy12
Jan 24, 2025Aspirant
ReadyNAS Ultra 6 RNDU6000 - ERR_SSL_VERSION_OR_CIPHER_MISMATCH
On a Windows 11 Home laptop, after following many suggested browser fixes with no luck, is there an issue with RAIDar 6.5.0 that will cause "ERR_SSL_VERSION_OR_CIPHER_MISMATCH" connection error?
The original version of RAIDar I used [4.3.8] also fails to work so I updated to 6.5.0.
Any suggestions to allow RAIDar to connect to the NAS correctly?
Cheers, Bruce.
3 Replies
- StephenBGuru - Experienced User
Reidy12 wrote:
On a Windows 11 Home laptop, after following many suggested browser fixes with no luck, is there an issue with RAIDar 6.5.0 that will cause "ERR_SSL_VERSION_OR_CIPHER_MISMATCH" connection error?
Any suggestions to allow RAIDar to connect to the NAS correctly?
The issue has nothing to do with RAIDar. The problem is that the NAS doesn't support TLS 1.2 - and browsers now require it.
You can add TLS 1.2 support to some ReadyNAS, for the others there are workarounds. What model NAS do you have, and what firmware is it running?
- Reidy12Aspirant
- StephenBGuru - Experienced User
Reidy12 wrote:
I appreciate your reply. See attached screenshot: basically ReadyNAS Ultra 6, Firmware 4.2.30
One option is to convert your NAS to run OS-6. You'd want to increase the RAM to 2 - 4 GB (inexpensive and easy to do). The conversion would require reformatting and your disks, and setting up the NAS from scratch - so you would need to back up the data. Among other things, the update would add support for SMB 3.1.
For now, you can connect to Frontview by using Firefox, and setting security.tls.version.min to 1 (browse to about:config and search for the setting). That setting will allow FireFox to connect using TLS 1.0.
After that, install this add-on to add TLS 1.2 support to your NAS:
Accessing the files with file explorer will also require that you enable the SMB 1.0/CIFS client on the PC - you can do that by going into "turn windows features on or off".
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