What is wrong with that server?

[aliassce]

Hello!

I programmed an ASP.NET site. It works quite well with Visual Web Developer. Also it has no problem at vwdhosting.net (free asp.net server).

My site includes photo uploading but because my server does not allow this I use "impersonate".

That's OK up to this point. But sometimes my pages causes errors, interestingly each time with a different one. For example a proper page may not work five minutes later. I'm really confused.

My server uses PLESK, and .NET 1.1

My codes are all suitable with .NET 1.1

I really want to understand how can a code cause problem after working properly several times.

Can it be a problem about the server?

Thanks in advance