Dude,

Dont short change yourself. From what I see, you have made the determination to jump and this is a good start. With your experience you should ask for RM3K and this is not really a big amount.

For me I think if you have the time and opportunity, you should go for a degree as many MNCs do favour a degree eventhough it is common. Kinda like the basic requirement.

2) what about my salary.. i know my qualification is quite low but with great responsibility i think i deserve better.
- This is a touchy issue. I believe u know how much your past admin was getting but u are not getting that amount. Somehow, there is an urge to tell the boss, but it is not as easy as it seems. Does ur MNC treat you well? How are the other benefits? Do you think other MNCs can give u a better deal? Is the working environment nice in ur current place?

3) what prof. cert. that i should get to enhance my qualification?
- Basically i feel a degree would help. I see u are already MCP. Perhaps u can try to sit another 3 more papers to make urself and MCSA.

4) how much salary i can get at other places?
For me I would ask for RM3K. However, the only factor that may pull you back is the degree. The HR can say that it is their policy that Diploma holders only earn a certain amount. Its unfair, but nothing much to do.