EMails - Cant reply, but can send out fine?

[FatRakoon]

Annoyingly one that I have not been able to sort out.

I get an EMail from MR "X", I try to reply, but it fails, telling me the recipients address was rejected by the sever.

So, I open the EMail up, get the EMail address of this MR "X", and create a new EMail and paste the EMail address in, and click on send and off it goes!!!

It has done this now for 2 weeks ( give or take a bit ) and I just cannot reply to a single EMail... I have only found out that I can do it this way.

Now...

I have 2 EMail adresses, my normal one and my GMail one. it does it with both these.

I am also suffering awfully slow internet and so, I have tried a different router ( 3 routers and 2 modems to be precise ) I have also reinstalled Windows on this PC, plus, I have tried 2 other PCs.

So, I know its not the PCs or the Routers that can possibly be at fault.

I have renewed the cables in and around the house, so its not that, and I have been in touch with my ISP who have said that they cannot find a fault. Seeing as its my business line that I am getting this problem with, and I have a fault repair guarantee that any faults are repaired within 24 hours, I think I can trust my ISP to be telling the truth on their part.

So, what the hell can be the problem?

General browsing is ok... Its definitely slower than it should be, but still ok.

SpeedTest.net gave me a 290K speed, but this cannot be possible because if I try to download anything, it drops even further ( Last week ,I downloaded the latest nVIDIA Drives and it took over 2 hours! ) - I have a 16MB Connection and normally, im floating about the 13-14 speeds.

Im completely stumped.

Anyone got any suggestions on my next course to take?


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ADDITION :-

Oh, Im on XP64 on this PC, and the other PC thats on 24Hours is running Vista32Ultimate, and thats has for the time being, been disconnected.

My router that I am currently toying about with, is a Linksys WAG 354G

I have disconnected all phones and the router is connected directly to the main phone inlet with no filter ( No need at this time )

 

[Sp00n]

What is the exact bounceback message?

 

[ns400r]

Have you recently swapped ISP's ?

If you connect to ISP number 1 and then try to send emails via ISP number 2 SMTP then it will most likely get rejected due to relaying errors.

Who do you use to connect to the internet and what address is one of the emails sent to that your trying to reply too?

 

[FatRakoon]

What is the exact bounceback message?

Have you recently swapped ISP's ?

If you connect to ISP number 1 and then try to send emails via ISP number 2 SMTP then it will most likely get rejected due to relaying errors.

Who do you use to connect to the internet and what address is one of the emails sent to that your trying to reply too?

I have managed a semi-cure for now.

I have my normal setup in Outlook Express, and my GMail setup, and now, I have set them both up to use the GMail account to send out.

This has cured it for now, or at least until my ISP gets their end sorted, or just gets back to me about it???

It just seems really strange that I can both SEND and RECEIVE but I am unable to REPLY?

Really silly that one?

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No, I have not changed anything over.

I did get an EMail a while back saying that I might need to change my SMTP over to managedbroad band and so I did this and it worked for a couple of days but then it failed again, so I put it back and it worked again for a couple of days but it failed again... I tried variating this, but nothing worked.

My ISP is XLN and the EMail addresses that fail to reply, are EVERYTHING.