Problem reading mime (.eml) attachments in mail on iOS 8 (all versions)

I am facing is in opening pdf/word/excel etc attachments inside a mime attachment received in email on the native email client on iPhone 5S (all versions of iOS, i.e iOS 7.1.2, iOS 8, iOS 8.1, iOS 8.1.2 or 8.1.3 as were released from time to time by Apple).

The pdf/ excel/ word etc attachments which are received in the main email are viewable/ readable without any problem. The problem comes when these attachments are enclosed inside a mime-attachment received in the main email.

This scenario happens typically when the sender forwards an email (with pdf/ excel/ word etc attachments) as as attachment, from a desktop PC either through a web browser based email client or through Outlook/ Mozilla Thunderbird type of mail Clients. In such cases the forwarded email appears as a mime attachment, with perhaps an .eml extension (although the extension is not visible on iPhone).

I have not faced any problem in opening the same emails/ mime attachments/ pdf etc attachments in Third party email softwares on the same iPhone (like Altamail available on iTunes Store ). All mime attachments and emails open without any problem in those third party email softwares on these iPhone.

It implies that the problem lies in native iPhone mail client and not the mail itself. The emails with mime attachments, under consideration, are perfectly visible and readable in all clients on desktop PCs. They are also readable/ viewable in Third Party softwares on the same iPhone.

It is also observed that the behaviour of erratic display of attachments has many different forms as described below:

(a) Sometimes, it shows attachment with size 0 Byte as was described earlier also, while at some other times, it shows garbled characters. Please note that all my content is in English language and there is no scope of any character other than English language. Hence the display of Garbled characters (possibly east asian characters) is also a cause for concern.

(b) Sometimes it shows nothing and gives the message that the attachment has not been downloaded from the server(in the case of the email which earlier has been downloaded). Sometimes it opens another window and just shows the name of the attachment (like a word file) but no content is displayed. Sometimes the same attachment shows with icon of Microsoft Word, but if you go back and reopen the same mail, the attachment may not show any icon and just say mime-attachment.

(c) Some times when there are more than one attachments inside the mime attachment, one attachment shows 0Byte size, while others show as if completely downloaded. Yet if you click those such seemingly completely downloaded attachments, nothing happens (no attachment opens). Further, if you go back and reopen the same mime attachment to view the attachments inside, they may all show 0 Byte size (where only one was showing as 0Byte size earlier).

(d) Sometimes the attachment opens to an incorrect file which was not sent with the mail, but is stored on the iPhone itself by way of some earlier emails.

The problem of attachments is faced with both wifi network as well as gprs network.